High-altitude headache and acute mountain sickness

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Robles Bayón, F. Gude Sampedro" "autores" => array:2 [ 0 => array:2 [ "nombre" => "A." "apellidos" => "Robles Bayón" ] 1 => array:2 [ "nombre" => "F." 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Carod-Artal" "autores" => array:1 [ 0 => array:3 [ "nombre" => "F.J." "apellidos" => "Carod-Artal" "email" => array:1 [ 0 => "fjcarod-artal@hotmail.com" ] ] ] "afiliaciones" => array:1 [ 0 => array:2 [ "entidad" => "Servicio de Neurología, Hospital Virgen de la Luz, Cuenca, Spain" "identificador" => "aff0005" ] ] ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Cefalea de elevada altitud y mal de altura" ] ] "textoCompleto" => "IntroductionThe first written record about high-altitude headache dates back to 30 BCE and is owed to Too Kin, an officer of the Imperial Chinese Army. Too Kin, along with his troops, experienced an episode of altitude sickness in a mountain range in Afghanistan which he named the Great Headache Mountain and the Little Headache Mountain.<a class="elsevierStyleCrossRef" href="#bib0005">1</a> Two millennia went by before Paul Bert, the chair of physiology at the Sorbonne after Claude Bernard, developed the modern discipline of altitude physiology.<a class="elsevierStyleCrossRef" href="#bib0010">2</a> In 1913, Thomas Ravenhill provided the first clinical descriptions of signs and symptoms associated with rapid ascent to high altitude in the north of Chile, and reported on both high-altitude cerebral oedema and high-altitude pulmonary oedema.<a class="elsevierStyleCrossRef" href="#bib0015">3</a>Headache is the most common complication of exposure to high altitude, and it can appear as isolated high-altitude headache (HAH) or in conjunction with acute mountain sickness (AMS). HAH is a global health problem whose incidence has increased over the past decades due to different factors. These include more opportunities for travel, exercise, and tourism which therefore expose thousands of tourists, travellers and sports enthusiasts to a rapid increase in altitude, frequently with no previous acclimation.<a class="elsevierStyleCrossRef" href="#bib0020">4</a> Exposure to altitude is considered high for subjects at elevations of 1500 to 3700m above sea level, very high at 3700 to 5500m, and extreme above 5500m.<a class="elsevierStyleCrossRef" href="#bib0025">5</a>However, a person with high altitude exposure can experience different types of headaches in addition to headache associated with altitude. This being the case, episodic migraine crises precipitated by hypoxia and altitude, as well as headache linked to acute mountain sickness, must be considered. The purpose of this article is to review several aspects related to diagnosis and treatment of HAH and AMS. To this end, we searched the Medline database for all articles published in English or Spanish up to February 2012, using the keywords ‘headache altitude’ and ‘acute mountain sickness’.High-altitude headacheEpidemiologyIt is estimated that at least 25% of non-acclimated individuals exposed to altitudes of 1859 to 2750m experience high-altitude headache. At altitudes above 3000m, 80% of individuals will have HAH and almost 100% will experience headache at 4500m or higher.<a class="elsevierStyleCrossRef" href="#bib0020">4</a>Definition, clinical presentation and risk factorsThe second edition of the International Classification of Headache Disorders (ICHD-II)<a class="elsevierStyleCrossRef" href="#bib0030">6</a> includes high-altitude headache (subsection 10.1.1) in chapter 10 (Headache attributed to disorder of homoeostasis), section 10.1 (Headache attributed to hypoxia and/or hypercapnia). Diagnostic criteria are listed in <a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>.<elsevierMultimedia ident="tbl0005"></elsevierMultimedia>HAH can appear as an isolated symptom within the first 24hours of exposure to altitudes above 2500m without previous acclimation, or it may present along with more varied signs and symptoms which constitute AMS, as we will discuss in a later section.<a class="elsevierStyleCrossRef" href="#bib0035">7</a>HAH has a mild to moderate intensity and can be described as bilateral dull or pressing pain in the frontal, frontoparietal, or holocranial regions.<a class="elsevierStyleCrossRefs" href="#bib0040">8,9</a> Clinically, this headache is usually aggravated by exertion and head or body movement. It may also present with throbbing pain which, according to different studies, affects 30%<a class="elsevierStyleCrossRef" href="#bib0040">8</a> to 75%<a class="elsevierStyleCrossRef" href="#bib0045">9</a> of individuals. Headaches either begin upon awakening, or wake subjects at night, in at least 25% of the cases. This type of headache seems to be more intense in women and in individuals with a history of other types of headache in daily life.<a class="elsevierStyleCrossRef" href="#bib0040">8</a>The connection between HAH and episodic migraine is yet to be determined. As pain in HAH seems to be more intense in patients with a previous history of migraine, some authors hypothesise that it may be associated with migraine.<a class="elsevierStyleCrossRef" href="#bib0040">8</a> Migraine without aura should be differentiated from HAH, especially in subjects with a prior history of migraine. It is believed that some cases of migraine with aura could be related to the presence of right-to-left shunt blood vessels that are increasingly active with physical exertion and altitude.<a class="elsevierStyleCrossRef" href="#bib0050">10</a> Doctors have also described isolated cases of primary cluster headache triggered by exposure to high altitude and responding to oxygen therapy.<a class="elsevierStyleCrossRef" href="#bib0055">11</a>Rapid ascent to a high altitude is the main risk factor.<a class="elsevierStyleCrossRefs" href="#bib0035">7,12–14</a> Known risk factors for HAH are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>. According to a study comprising 506 mountaineers who experienced headache at altitudes of 2200 to 3817m, risk factors for HAH were previous history of migraine, intense physical exertion, and low arterial oxygen saturation.<a class="elsevierStyleCrossRef" href="#bib0070">14</a> Adults and the elderly have a lower incidence of headache than the younger population, which may be due to the effect of cerebral atrophy. A good level of physical fitness (‘being fit’) does not prevent HAH.<elsevierMultimedia ident="tbl0010"></elsevierMultimedia>PathogenesisThere is an inverse relationship between altitude/atmospheric pressure and PaO2. Chemoreceptors in the carotid body of a person gaining altitude detect a reduction in PaO2. Hypoxia promotes a neurohumoral and haemodynamic response that gives rise to increased capillary pressure and vascular and cerebral oedema. Hypoxia-induced cerebral vasodilation is a probable cause of headache. Cerebral blood flow is elevated in the hypoxic state and returns to pre-ascent values with acclimation.<a class="elsevierStyleCrossRef" href="#bib0035">7</a>Cerebral autoregulation, a process aimed at regulating cerebral perfusion according to variations in blood pressure, is altered by hypoxia and in individuals suffering from HAH and AMS.<a class="elsevierStyleCrossRef" href="#bib0075">15</a> Studies performed with transcranial Doppler, which measures velocity in the middle cerebral artery (MCA) as an indicator of cerebral blood flow, show considerable variations in flow velocity.<a class="elsevierStyleCrossRef" href="#bib0080">16</a> Sea-level assessment of dynamic cerebral autoregulation, which uses transcranial Doppler to calculate velocity in the MCA, can act as a predictor for susceptibility to AMS.<a class="elsevierStyleCrossRef" href="#bib0085">17</a> A lower baseline autoregulation index may be considered a potential risk factor for AMS.However, researchers have also proposed other factors apart from hypobaric hypoxia that favour HAH, for example, alterations in the blood-brain barrier promoted by different mediators, such as vascular endothelial growth factor, nitric oxide, or bradykinin.<a class="elsevierStyleCrossRef" href="#bib0020">4</a> Some also suggest that the trigeminovascular system may be activated at high altitude by either chemical stimuli (nitric oxide) or mechanical stimuli (vasodilation).<a class="elsevierStyleCrossRef" href="#bib0090">18</a>DiagnosisFor HAH to be diagnosed, the condition must appear at altitudes above 2500m and it may not be attributable to other causes. For this reason, differential diagnosis for HAH must consider an array of toxic and metabolic causes and space-occupying cerebral lesions listed in <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>. The differential diagnosis commonly includes headache due to viral infections and dehydration.<a class="elsevierStyleCrossRef" href="#bib0095">19</a><elsevierMultimedia ident="tbl0015"></elsevierMultimedia>Acute mountain sicknessEpidemiologyIncidence of AMS is approximately 45% to 95%, depending on the series. It is estimated that almost 50% of trekkers ascending above 5000m experience acute mountain sickness.<a class="elsevierStyleCrossRef" href="#bib0100">20</a>AcclimationImmediate physiological changes induced by hypoxia and altitude include increases in heart and respiratory rates, increased diuresis, alterations in taste perception, nasal congestion, and sometimes syncope. Acclimation can be considered the final stage of a process in which individuals adapt to altitude hypoxia. While acclimation takes several days to weeks, symptoms of AMS present at the onset of this process.<a class="elsevierStyleCrossRef" href="#bib0035">7</a>SymptomsThe main symptom of AMS is headache, frequently accompanied by sleep disorders, fatigue, dizziness and instability, nausea, and anorexia. Insomnia is the second most frequent symptom and presents in at least 60% of all individuals reaching 3500m. Non-restorative sleep may be secondary to periodic breathing that interrupts sleep architecture with a pattern of hypoxia-hyperventilation-hypocapnia; other factors such as headache and fatigue may also promote insomnia.<a class="elsevierStyleCrossRef" href="#bib0105">21</a> High-altitude syncope seems to be a vasovagal phenomenon related to hypoxia, although at times the presence of arrhythmias may trigger it.<a class="elsevierStyleCrossRef" href="#bib0110">22</a>The frequency and intensity of symptoms associated with AMS seem to point to some degree of individual susceptibility and considerable inter-individual variability. For this reason it is believed that there may be a certain genetic predisposition to AMS. In any case, human response to hypobaric hypoxia seems to be polygenic<a class="elsevierStyleCrossRef" href="#bib0115">23</a> and determined by different expression of genes encoding different proteins, such as serum erythropoietin, hypoxia-inducible factor 1alpha (HIF-1alpha), angiotensin-converting enzyme, aldosterone, and nitric oxide synthase activity, among others.<a class="elsevierStyleCrossRef" href="#bib0020">4</a>PathophysiologyFrom a pathophysiological point of view, the main pathogenetic factor in acute mountain sickness is hypobaric hypoxia, which can be exacerbated by hypoventilation, a periodic breathing pattern, and relatively intense physical exertion. The combination of these factors leads to an increase in capillary permeability, sodium retention, vasodilation, and an increase in cerebral blood flow and pulmonary hypertension.<a class="elsevierStyleCrossRef" href="#bib0120">24</a>Apart from O2 and CO2 concentrations, several factors can affect blood vessel tonicity in hypoxia, mainly cerebral adenosine, potassium ion, and nitric oxide synthase levels. Vascular permeability may be influenced not only by hypoxia but also by different chemical mediators, such as hypoxia-inducible factor 1 (HIF-1)<a class="elsevierStyleCrossRef" href="#bib0125">25</a> and vascular endothelial growth factor (VEGF).<a class="elsevierStyleCrossRef" href="#bib0130">26</a>DiagnosisThe Lake Louise AMS scoring system was developed for establishing an early diagnosis and monitoring severity of AMS symptoms in individuals exposed to high altitudes.<a class="elsevierStyleCrossRef" href="#bib0135">27</a> It consists of 2 sections, a self-reported questionnaire and a clinical assessment form. A diagnosis of AMS requires the presence of the main symptom, headache (even when it presents with mild intensity), plus at least 1 additional symptom.Diagnostic criteria for AMS by Lake Louise Consensus Group are listed in <a class="elsevierStyleCrossRef" href="#tbl0020">Table 4</a>. Scores of 3 to 5 on the questionnaire indicate mild AMS and scores of 6 or more indicate severe AMS.<a class="elsevierStyleCrossRef" href="#bib0140">28</a> An adapted Spanish version of the Lake Louise AMS questionnaire was validated a few years ago.<a class="elsevierStyleCrossRef" href="#bib0145">29</a> The Environmental Symptoms Questionnaire is a more detailed and time-consuming questionnaire that may be useful for assessing severity of AMS symptoms in applied research.<a class="elsevierStyleCrossRef" href="#bib0150">30</a><elsevierMultimedia ident="tbl0020"></elsevierMultimedia>High-altitude cerebral oedemaEpidemiologyHigh-altitude cerebral oedema (HACE) is the most severe form of AMS. It may occur above 2500m and should therefore be considered in differential diagnosis of HAH. HACE is a potentially highly severe encephalopathy that may affect 0.5% to 1% of all individuals suffering from AMS.<a class="elsevierStyleCrossRef" href="#bib0155">31</a> In addition, it is estimated that 5% of non-acclimated individuals may present cerebral oedema above 4500m. The incidence of high-altitude pulmonary oedema is approximately 2%.<a class="elsevierStyleCrossRef" href="#bib0160">32</a>SymptomsThe mildest forms of cerebral oedema present with headache, dizziness, vertigo, and reaction time retardation. The most severe forms can present with ataxia, altered level of consciousness, hallucinations, seizures, stupor, and coma. Above 7500m, 32% of climbers experience hallucinations. An increase in intracranial pressure may lead to papilloedema, retinal haemorrhage and paralysis of cranial nerves, especially cranial nerve VI. The most severe forms may progress to cerebral herniation, and intracranial hypertension resulting in death.<a class="elsevierStyleCrossRef" href="#bib0165">33</a> Retinal haemorrhages, which are frequent during high-altitude ascent, occur in 30% and 50% of individuals suffering from AMS and HACE, respectively.<a class="elsevierStyleCrossRef" href="#bib0170">34</a>Neuroimaging findingsNeuroimaging studies (cerebral computed tomography and brain magnetic resonance imaging) showed small ventricles and cerebral sulci effacement in climbers suffering HACE. It is not yet known whether cerebral oedema is of vasogenic or cytotoxic origin, or whether one precedes the other or if both present simultaneously.<a class="elsevierStyleCrossRef" href="#bib0035">7</a> Hypoxia may produce a generalised vasogenic oedema subsequent to an increase in blood-brain barrier permeability. However, both cytotoxic<a class="elsevierStyleCrossRef" href="#bib0175">35</a> and vasogenic<a class="elsevierStyleCrossRef" href="#bib0180">36</a> cellular oedema have been detected. Cytotoxic oedema may derive from disorders in ATP-dependent sodium-potassium pump functioning.Individuals suffering from high-altitude cerebral and pulmonary oedema showed hyperintense areas in the splenium of the corpus callosum and in the centrum semiovale, but no abnormalities in cortical grey matter.<a class="elsevierStyleCrossRef" href="#bib0120">24</a> On this basis, many authors suggest that high-altitude cerebral oedema is predominantly a reversible vasogenic cerebral oedema in the white matter.<a class="elsevierStyleCrossRef" href="#bib0180">36</a> Brain MRI has also shown hyperintensities in subcortical white matter in individuals above 7000m.<a class="elsevierStyleCrossRef" href="#bib0180">36</a>Additional brain MRI studies in HACE patients revealed haemosiderin depositions, mostly in the corpus callosum.<a class="elsevierStyleCrossRef" href="#bib0185">37</a>PathogenesisHACE pathogenesis has traditionally been based on the theory of intracranial hypertension secondary to hypobaric hypoxia. However, some authors have stated that correlation between headache in AMS and cerebral oedema is unclear.<a class="elsevierStyleCrossRef" href="#bib0020">4</a> It has recently been suggested that hypoxia may affect not only cerebral blood flow, but also cause a certain degree of cerebral venous insufficiency. Thus, a slight increase in central venous pressure (as occurs with hypoxia-induced pulmonary vasoconstriction, for example) may compromise cerebral venous outflow at high altitudes and favour oedema.<a class="elsevierStyleCrossRef" href="#bib0190">38</a> Cerebral oedema is considered the main factor leading to increased brain volume and intracranial hypertension. However, there are other mechanisms, such as increases in cerebral blood flow or venous outflow obstruction, which may also increase intracranial pressure.Other neurological and neuropsychological complications associated with high altitudeCerebrovascular complications described in association with high altitude include transient ischaemic attack and ischaemic stroke. Their origin may be related to vasospasm and vasoconstriction phenomena favoured by the hypocapnia, severe dehydration, and thrombophilia associated with hypoxia.<a class="elsevierStyleCrossRef" href="#bib0195">39</a> Some cases of patients who died at high altitude due to cerebral venous thrombosis can be found in medical literature.<a class="elsevierStyleCrossRef" href="#bib0200">40</a> Histopathological and postmortem examinations have confirmed the presence of ring-shaped microhaemorrhages associated with cerebral venous thrombosis.<a class="elsevierStyleCrossRefs" href="#bib0120">24,40,41</a>Exposure to hypobaric hypoxia leads to neuropsychological disturbances in perception, memory, language, reaction time, learning, and psychomotor skills. Learning capacity, short-term memory and spatial memory are affected at altitudes above 4500m, and more profoundly at more than 6000m. Symptom intensity varies according to ascent rate and altitude.<a class="elsevierStyleCrossRefs" href="#bib0210">42,43</a>TreatmentHigh-altitude headachePharmacological treatment in the acute phase must distinguish isolated headache in AMS from cerebral oedema. As HAH is frequently self-limited and remits in 2 or 3 days, climbers are recommended to stop climbing, rest, and rehydrate when the condition presents. If symptoms persist or worsen, climbers should descend 500 to 1000m.<a class="elsevierStyleCrossRef" href="#bib0025">5</a> Adequate hydration, analgesics and anti-inflammatory agents may improve symptoms.<a class="elsevierStyleCrossRef" href="#bib0095">19</a>HAH can be treated with paracetamol (500-1000mg) and anti-inflammatory agents such as ibuprofen (400-600mg).<a class="elsevierStyleCrossRefs" href="#bib0095">19,44</a> Triptans are not effective, although they can be useful for migraine associated with hypoxia. At extreme altitudes, supplementary oxygen (2-4L/minute) may be necessary during the night.<a class="elsevierStyleCrossRef" href="#bib0035">7</a> Once oxygen therapy has been administered, HAH should improve within about 15 minutes; this event may be an indicator for ruling out migraine.Acute mountain sickness and cerebral oedemaPharmacological treatment of AMS is intended to increase ventilatory drive with drugs such as acetazolamide, and reduce inflammation and cytokine release by means of steroids.Acetazolamide is a carbonic anhydrase inhibitor that acts on the brain in addition to the blood cells, renal tubules, chemoreceptors, and systemic and pulmonary vessels. It provokes metabolic acidosis, thus increasing respiratory minute volume. Cerebral oedema can be treated with acetazolamide (125-250mg every 8-12h),<a class="elsevierStyleCrossRef" href="#bib0225">45</a> dexamethasone (4mg/6h, orally),<a class="elsevierStyleCrossRef" href="#bib0230">46</a> and/or portable hyperbaric chamber (193mbar during 1h),<a class="elsevierStyleCrossRef" href="#bib0235">47</a> depending on intensity and severity of symptoms.<a class="elsevierStyleCrossRef" href="#bib0240">48</a> Dexamethasone seems to block VEGF expression and reverts hypoxia-induced cerebral oedema.<a class="elsevierStyleCrossRef" href="#bib0245">49</a>PreventionHigh-altitude headacheA slow ascent which promotes acclimation is recommended. At 2500m and above, the maximum advisable ascent rate would be approximately 600m per day. This may reduce the incidence of AMS by 40%. Diet is also important and should be based on carbohydrates. Alcohol should be avoided.Results from the HEAT trial (Headache Evaluation at Altitude Trial) were published recently; this clinical trial compared the effects of 600mg ibuprofen or 85mg acetazolamide or placebo for preventing HAH in 343 healthy subjects at 4300m.<a class="elsevierStyleCrossRef" href="#bib0250">50</a> Headache incidence rates were similar in participants treated with acetazolamide (27.1%) or ibuprofen (27.5%), and both were lower than that among participants receiving the placebo (45.3%). This suggests that both drugs in such doses are equally efficacious against HAH.<a class="elsevierStyleCrossRef" href="#bib0250">50</a>Acute mountain sicknessIndividuals ascending above 3000m or with a previous history of AMS-associated headache are recommended to take acetazolamide as preventive treatment. The recommended preventive dosage is 125 to 250mg every 12hours, at least 24hours before ascent and for 2 days while the subject is at high altitude.<a class="elsevierStyleCrossRefs" href="#bib0240">48,51</a> Higher doses (375mg every 12hours) do not seem to be more efficacious than a dose of 125mg every 12hours.<a class="elsevierStyleCrossRef" href="#bib0260">52</a> However, results from the SPACE trial (spironolactone and acetazolamide trial in the prevention of acute mountain sickness) showed that spironolactone does not seem to prevent AMS compared to results from acetazolamide.<a class="elsevierStyleCrossRef" href="#bib0265">53</a>Dexamethasone (8mg per day, administered in several doses) is effective for preventing AMS because it reduces cytokine-release and capillary permeability.<a class="elsevierStyleCrossRef" href="#bib0270">54</a> Prednisolone at a dose of 20mg every 24hours for 2 days before ascent and 3 days while at high altitude is also beneficial.<a class="elsevierStyleCrossRef" href="#bib0275">55</a>Ginkgo biloba extracts have been used to promote free radical elimination and prevent AMS. However, the PHAIT trial (prevention of high altitude illness trial) showed that it does not seem to be efficacious for preventing AMS compared to results from acetazolamide.<a class="elsevierStyleCrossRef" href="#bib0280">56</a> Aspirin, at a dose of 325mg three times daily, seems to reduce the incidence of headache associated with physical exertion at high altitude.<a class="elsevierStyleCrossRef" href="#bib0285">57</a> Different recommendations on preventive measures for HAH, are listed in <a class="elsevierStyleCrossRef" href="#tbl0025">Table 5</a> according to level of evidence.<elsevierMultimedia ident="tbl0025"></elsevierMultimedia>We need new clinical trials to confirm whether sumatriptan, dosed at 50mg before ascent, is efficacious for preventing AMS.<a class="elsevierStyleCrossRef" href="#bib0290">58</a> Additional trials will have to confirm the results of a small study that found that low doses of theophylline (300mg per day for 5 days) were efficacious for preventing AMS.<a class="elsevierStyleCrossRef" href="#bib0295">59</a>ConclusionHAH can occur in isolation or as the main symptom of AMS. In any case, clinical symptoms seem to display a progressive pattern along the continuum of HAH, AMS, and HACE. At present, the recent discoveries of different chemical mediators provide us with a better understanding of the pathogenesis of this continuum and of the therapeutic targets acted upon by acetazolamide and steroids.Conflicts of interestThe author has no conflicts of interest to declare." "textoCompletoSecciones" => array:1 [ "secciones" => array:14 [ 0 => array:2 [ "identificador" => "xres382747" "titulo" => array:4 [ 0 => "Abstract" 1 => "Introduction" 2 => "Development" 3 => "Conclusions" ] ] 1 => array:2 [ "identificador" => "xpalclavsec361647" "titulo" => "Keywords" ] 2 => array:2 [ "identificador" => "xres382748" "titulo" => array:4 [ 0 => "Resumen" 1 => "Introducción" 2 => "Desarrollo" 3 => "Conclusiones" ] ] 3 => array:2 [ "identificador" => "xpalclavsec361648" "titulo" => "Palabras clave" ] 4 => array:2 [ "identificador" => "sec0005" "titulo" => "Introduction" ] 5 => array:3 [ "identificador" => "sec0010" "titulo" => "High-altitude headache" "secciones" => array:4 [ 0 => array:2 [ "identificador" => "sec0015" "titulo" => "Epidemiology" ] 1 => array:2 [ "identificador" => "sec0020" "titulo" => "Definition, clinical presentation and risk factors" ] 2 => array:2 [ "identificador" => "sec0025" "titulo" => "Pathogenesis" ] 3 => array:2 [ "identificador" => "sec0030" "titulo" => "Diagnosis" ] ] ] 6 => array:3 [ "identificador" => "sec0035" "titulo" => "Acute mountain sickness" "secciones" => array:5 [ 0 => array:2 [ "identificador" => "sec0040" "titulo" => "Epidemiology" ] 1 => array:2 [ "identificador" => "sec0045" "titulo" => "Acclimation" ] 2 => array:2 [ "identificador" => "sec0050" "titulo" => "Symptoms" ] 3 => array:2 [ "identificador" => "sec0055" "titulo" => "Pathophysiology" ] 4 => array:2 [ "identificador" => "sec0060" "titulo" => "Diagnosis" ] ] ] 7 => array:3 [ "identificador" => "sec0065" "titulo" => "High-altitude cerebral oedema" "secciones" => array:4 [ 0 => array:2 [ "identificador" => "sec0070" "titulo" => "Epidemiology" ] 1 => array:2 [ "identificador" => "sec0075" "titulo" => "Symptoms" ] 2 => array:2 [ "identificador" => "sec0080" "titulo" => "Neuroimaging findings" ] 3 => array:2 [ "identificador" => "sec0085" "titulo" => "Pathogenesis" ] ] ] 8 => array:2 [ "identificador" => "sec0145" "titulo" => "Other neurological and neuropsychological complications associated with high altitude" ] 9 => array:3 [ "identificador" => "sec0095" "titulo" => "Treatment" "secciones" => array:2 [ 0 => array:2 [ "identificador" => "sec0100" "titulo" => "High-altitude headache" ] 1 => array:2 [ "identificador" => "sec0105" "titulo" => "Acute mountain sickness and cerebral oedema" ] ] ] 10 => array:3 [ "identificador" => "sec0135" "titulo" => "Prevention" "secciones" => array:2 [ 0 => array:2 [ "identificador" => "sec0140" "titulo" => "High-altitude headache" ] 1 => array:2 [ "identificador" => "sec0120" "titulo" => "Acute mountain sickness" ] ] ] 11 => array:2 [ "identificador" => "sec0125" "titulo" => "Conclusion" ] 12 => array:2 [ "identificador" => "sec0130" "titulo" => "Conflicts of interest" ] 13 => array:1 [ "titulo" => "References" ] ] ] "pdfFichero" => "main.pdf" "tienePdf" => true "fechaRecibido" => "2012-03-12" "fechaAceptado" => "2012-04-21" "PalabrasClave" => array:2 [ "en" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Keywords" "identificador" => "xpalclavsec361647" "palabras" => array:6 [ 0 => "Altitude" 1 => "Acetazolamide" 2 => "Headache" 3 => "Lake Louise Questionnaire" 4 => "Cerebral oedema" 5 => "Acute mountain sickness" ] ] ] "es" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Palabras clave" "identificador" => "xpalclavsec361648" "palabras" => array:6 [ 0 => "Altitud" 1 => "Acetazolamida" 2 => "Cefalea" 3 => "Cuestionario Lago Louise" 4 => "Edema cerebral de altitud" 5 => "Mal de altura" ] ] ] ] "tieneResumen" => true "resumen" => array:2 [ "en" => array:2 [ "titulo" => "Abstract" "resumen" => "IntroductionHeadache is the most common complication associated with exposure to high altitude, and can appear as an isolated high-altitude headache (HAH) or in conjunction with acute mountain sickness (AMS). The purpose of this article is to review several aspects related to diagnosis and treatment of HAH. DevelopmentHAH occurs in 80% of all individuals at altitudes higher than 3000m. The second edition of ICHD-II includes HAH in the chapter entitled “Headaches attributed to disorder of homeostasis”. Hypoxia elicits a neurohumoral and haemodynamic response that may provoke increased capillary pressure and oedema. Hypoxia-induced cerebral vasodilation is a probable cause of HAH. The main symptom of AMS is headache, frequently accompanied by sleep disorders, fatigue, dizziness and instability, nausea and anorexia. Some degree of individual susceptibility and considerable inter-individual variability seem to be present in AMS. High-altitude cerebral oedema is the most severe form of AMS, and may occur above 2500m. Brain MRI studies have found variable degrees of oedema in subcortical white matter and the splenium of the corpus callosum. HAH can be treated with paracetamol or ibuprofen. Pharmacological treatment of AMS is intended to increase ventilatory drive with drugs such as acetazolamide, and reduce inflammation and cytokine release by means of steroids. ConclusionsSymptom escalation seems to be present along the continuum containing HAH, AMS, and high-altitude cerebral oedema." ] "es" => array:2 [ "titulo" => "Resumen" "resumen" => "IntroducciónLa cefalea es la complicación más frecuente de la exposición a la altitud y puede aparecer de forma aislada o bien asociada al mal de altura (MA). El objetivo de este artículo es revisar los aspectos relacionados con el diagnóstico y tratamiento de la cefalea de elevada altitud (CEA). DesarrolloEl 80% de las personas presentan CEA por encima de los 3.000m de altitud. La segunda versión de la Internacional Classification of Headache Disorders (ICHD-II) incluye la CEA en el capítulo «Cefalea atribuida a trastornos de la homeostasia». La hipoxia desencadena una respuesta neurohumoral y hemodinámica que provoca un aumento de la presión capilar y edema. La vasodilatación cerebral inducida por hipoxia es una causa probable de CEA. El síntoma cardinal del MA es la cefalea, que se suele asociar con trastornos del sueño, fatiga, mareo e inestabilidad, náuseas y anorexia. Parece existir una cierta susceptibilidad así como una gran variación interindividual. La forma más grave es el edema cerebral de altitud y puede suceder por encima de los 2.500m. Estudios de resonancia de encéfalo han mostrado la presencia de edema en sustancia blanca y esplenio del cuerpo calloso. La CEA puede tratarse con paracetamol e ibuprofeno. El tratamiento farmacológico del MA tiene la finalidad de incrementar la respuesta ventilatoria, mediante fármacos como la acetazolamida, y reducir los procesos inflamatorios y de liberación de citocinas, mediante el empleo de esteroides. ConclusionesParece haber una progresión en la expresión de los síntomas entre la CEA, el MA y el edema cerebral de altitud." ] ] "NotaPie" => array:2 [ 0 => array:2 [ "etiqueta" => "☆" "nota" => "Please cite this article as: Carod-Artal FJ. Cefalea de elevada altitud y mal de altura. Neurología. 2014;29:533–540." ] 1 => array:2 [ "etiqueta" => "☆☆" "nota" => "This study was presented as a lecture to the Headache Study Group at the 63rd Annual Meeting of the Spanish Society of Neurology, November 2011, Barcelona." ] ] "multimedia" => array:5 [ 0 => array:7 [ "identificador" => "tbl0005" "etiqueta" => "Table 1" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">A. Headache must present with at least 2 of the following characteristics and fulfil criteria C and D: \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1. Bilateral \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2. Frontal or frontotemporal \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3. Dull or pressing pain \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">4. Mild to moderate intensity \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">5. Aggravated by exertion, movement, straining, coughing, or bending down \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">B. Ascent to altitudes above 2500m \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">C. Headache develops within 24hours after ascent \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">D. Headache resolves within 8hours after descent \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab584436.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Diagnostic criteria for HAH" ] ] 1 => array:7 [ "identificador" => "tbl0010" "etiqueta" => "Table 2" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "tabla" => array:2 [ "leyenda" => "masl: metres above sea level." "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Altitude reached \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Sleeping at high altitude \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Individual susceptibility \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Rate and mode of ascent \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Prior history of AMS \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Residence below 900masl \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Intense exertion \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Dehydration \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Obesity \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Age (young people) \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">History of cardiopulmonary disease \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab584435.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Risk factors for HAH" ] ] 2 => array:7 [ "identificador" => "tbl0015" "etiqueta" => "Table 3" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Cerebral oedema/severe AMS \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Hypoxia-/hypobaria-induced migraine \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Headache secondary to viral process \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Effects associated with alcohol, addictive drugs, and toxic chemicals \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Carbon monoxide poisoning \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Brain tumour \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Arteriovenous malformations \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">CNS infection \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Dehydration \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Metabolic disorders \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Diabetic ketoacidosis \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Hypothermia \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Hyponatraemia/hypoglycaemia \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab584434.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Differential diagnosis for HAH" ] ] 3 => array:7 [ "identificador" => "tbl0020" "etiqueta" => "Table 4" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "tabla" => array:2 [ "leyenda" => "masl: metres above sea level." "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Headache in non-acclimated individuals who ascend rapidly to an altitude above 2500m, and at least 1 of the following symptoms: \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">- Gastrointestinal: anorexia, nausea and vomiting \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">- Insomnia \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">- Dizziness/vertigo \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">- Fatigue \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">- Onset within 6-24hours after ascent, sometimes within the first hour \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab584432.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Lake Louise diagnostic criteria for AMS" ] ] 4 => array:7 [ "identificador" => "tbl0025" "etiqueta" => "Table 5" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "tabla" => array:2 [ "leyenda" => "masl: metres above sea level." "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" style="border-bottom: 2px solid black">Procedure \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" style="border-bottom: 2px solid black">Dose \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" style="border-bottom: 2px solid black">Evidence \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" style="border-bottom: 2px solid black">Recommendations \t\t\t\t\t\t\n \t\t\t\t</td></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Slow ascent \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><300masl \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">A \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Acetazolamide \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">250mg to 1g \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">A \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Dexamethasone \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8mg/d \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">A \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Supplementary O2 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2L/min \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">A \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Theophylline \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">375mg/12h \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">B \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Sumatriptan \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">50mg \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">B \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Carbohydrate-rich diet \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">C \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Ginkgo biloba \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">240mg/d \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">C \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab584433.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Recommended preventive measures for HAH according to the level of evidence" ] ] ] "bibliografia" => array:2 [ "titulo" => "References" "seccion" => array:1 [ 0 => array:2 [ "identificador" => "bibs0005" "bibliografiaReferencia" => array:59 [ 0 => array:3 [ "identificador" => "bib0005" "etiqueta" => "1" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The great breathlessness mountains" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "D. Rennie" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J Am Med Assoc" "fecha" => "1986" "volumen" => "256" "paginaInicial" => "81" "paginaFinal" => "82" ] ] ] ] ] ] 1 => array:3 [ "identificador" => "bib0010" "etiqueta" => "2" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "La pression barometrique" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "P. Bert" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:3 [ "fecha" => "1878" "editorial" => "G Masson" "editorialLocalizacion" => "Paris" ] ] ] ] ] ] 2 => array:3 [ "identificador" => "bib0015" "etiqueta" => "3" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Some experiences of mountain sickness in the Andes" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "T.H. Ravenhill" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J Trop Med Hyg" "fecha" => "1913" "volumen" => "16" "paginaInicial" => "313" "paginaFinal" => "320" ] ] ] ] ] ] 3 => array:3 [ "identificador" => "bib0020" "etiqueta" => "4" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The cerebral effects of ascent to high altitudes" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "M.H. Wilson" 1 => "S. Newman" 2 => "C.H. Imray" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/S1474-4422(09)70014-6" "Revista" => array:6 [ "tituloSerie" => "Lancet Neurol" "fecha" => "2009" "volumen" => "8" "paginaInicial" => "175" "paginaFinal" => "191" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/19161909" "web" => "Medline" ] ] ] ] ] ] ] ] 4 => array:3 [ "identificador" => "bib0025" "etiqueta" => "5" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High-altitude illness" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "P.H. Hackett" 1 => "R.C. Roach" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1056/NEJM200107123450206" "Revista" => array:6 [ "tituloSerie" => "N Engl J Med" "fecha" => "2001" "volumen" => "345" "paginaInicial" => "107" "paginaFinal" => "114" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/11450659" "web" => "Medline" ] ] ] ] ] ] ] ] 5 => array:3 [ "identificador" => "bib0030" "etiqueta" => "6" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The International Classification of Headache Disorders, 2nd edition" "autores" => array:1 [ 0 => array:2 [ "colaboracion" => "Headache Classification Subcommittee of the International Headache Society" "etal" => false ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Cephalalgia" "fecha" => "2004" "volumen" => "24" "numero" => "Suppl. 1" "paginaInicial" => "S9" "paginaFinal" => "S151" ] ] ] ] ] ] 6 => array:3 [ "identificador" => "bib0035" "etiqueta" => "7" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Acute mountain sickness: pathophysiology, prevention, and treatment" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "C. Imray" 1 => "A. Wright" 2 => "A. Subudhi" 3 => "R. Roach" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/j.pcad.2010.02.003" "Revista" => array:6 [ "tituloSerie" => "Prog Cardiovasc Dis" "fecha" => "2010" "volumen" => "52" "paginaInicial" => "467" "paginaFinal" => "484" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/20417340" "web" => "Medline" ] ] ] ] ] ] ] ] 7 => array:3 [ "identificador" => "bib0040" "etiqueta" => "8" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Clinical features of headache at altitude: a prospective study" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "E. Silber" 1 => "P. Sonnenberg" 2 => "D.J. Collier" 3 => "A.J. Pollar" 4 => "D.R. Murdoch" 5 => "P.J. Goadsby" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Neurology" "fecha" => "2003" "volumen" => "60" "paginaInicial" => "1167" "paginaFinal" => "1171" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12682326" "web" => "Medline" ] ] ] ] ] ] ] ] 8 => array:3 [ "identificador" => "bib0045" "etiqueta" => "9" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High altitude headache. A prospective study of its clinical characteristics" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "M. Serrano Dueñas" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1111/j.1468-2982.2005.00968.x" "Revista" => array:6 [ "tituloSerie" => "Cephalalgia" "fecha" => "2005" "volumen" => "25" "paginaInicial" => "1110" "paginaFinal" => "1116" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16305599" "web" => "Medline" ] ] ] ] ] ] ] ] 9 => array:3 [ "identificador" => "bib0050" "etiqueta" => "10" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Intrapulmonary and intracardiac shunting with exercise at altitude" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "C.H. Imray" 1 => "K.T. Pattinson" 2 => "S. Myers" 3 => "C.W. Chan" 4 => "H. Hoar" 5 => "S. Brearey" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1580/07-WEME-BR-162.1" "Revista" => array:6 [ "tituloSerie" => "Wilderness Environ Med" "fecha" => "2008" "volumen" => "19" "paginaInicial" => "199" "paginaFinal" => "204" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18715120" "web" => "Medline" ] ] ] ] ] ] ] ] 10 => array:3 [ "identificador" => "bib0055" "etiqueta" => "11" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Efficacy of oxygen inhalation in sumatriptan refractory “high altitude” cluster headache attacks" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:5 [ 0 => "E. Mampreso" 1 => "F. Maggioni" 2 => "F. Viaro" 3 => "C. Disco" 4 => "G. Zanchin" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1007/s10194-009-0160-0" "Revista" => array:6 [ "tituloSerie" => "J Headache Pain" "fecha" => "2009" "volumen" => "10" "paginaInicial" => "465" "paginaFinal" => "467" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/19779957" "web" => "Medline" ] ] ] ] ] ] ] ] 11 => array:3 [ "identificador" => "bib0060" "etiqueta" => "12" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Determinants of acute mountain sickness and success on Mount Aconcagua (6962m)" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "C. Pesce" 1 => "C. Leal" 2 => "H. Pinto" 3 => "G. González" 4 => "M. Maggiorini" 5 => "M. Schneider" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/ham.2005.6.158" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2005" "volumen" => "6" "paginaInicial" => "158" "paginaFinal" => "166" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16060850" "web" => "Medline" ] ] ] ] ] ] ] ] 12 => array:3 [ "identificador" => "bib0065" "etiqueta" => "13" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Identifying the possible risk factors for high-altitude headache in mountaineers" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "J.S. Lawley" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1177/0333102411422385" "Revista" => array:6 [ "tituloSerie" => "Cephalalgia" "fecha" => "2011" "volumen" => "31" "paginaInicial" => "1677" "paginaFinal" => "1678" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21926157" "web" => "Medline" ] ] ] ] ] ] ] ] 13 => array:3 [ "identificador" => "bib0070" "etiqueta" => "14" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Risk factors for high-altitude headache in mountaineers" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "M. Burtscher" 1 => "K. Mairer" 2 => "M. Wille" 3 => "G. Broessner" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1177/0333102410394678" "Revista" => array:6 [ "tituloSerie" => "Cephalalgia" "fecha" => "2011" "volumen" => "31" "paginaInicial" => "706" "paginaFinal" => "711" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21220379" "web" => "Medline" ] ] ] ] ] ] ] ] 14 => array:3 [ "identificador" => "bib0075" "etiqueta" => "15" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Effects of high altitude exposure on cerebral hemodynamics in normal subjects" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "A. Van Osta" 1 => "J.J. Moraine" 2 => "C. Mélot" 3 => "H. Mairbäurl" 4 => "M. Maggiorini" 5 => "R. Naeije" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1161/01.STR.0000155735.85888.13" "Revista" => array:6 [ "tituloSerie" => "Stroke" "fecha" => "2005" "volumen" => "36" "paginaInicial" => "557" "paginaFinal" => "560" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15692117" "web" => "Medline" ] ] ] ] ] ] ] ] 15 => array:3 [ "identificador" => "bib0080" "etiqueta" => "16" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Cerebral artery dilatation maintains cerebral oxygenation at extreme altitude and in acute hypoxia – an ultrasound and MRI study" "autores" => array:1 [ 0 => array:3 [ "colaboracion" => "Caudwell Xtreme Everest Research Group" "etal" => true "autores" => array:6 [ 0 => "M.H. Wilson" 1 => "M.E. Edsell" 2 => "I. Davagnanam" 3 => "S.P. Hirani" 4 => "D.S. Martin" 5 => "D.Z. Levett" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1038/jcbfm.2011.81" "Revista" => array:6 [ "tituloSerie" => "J Cereb Blood Flow Metab" "fecha" => "2011" "volumen" => "31" "paginaInicial" => "2019" "paginaFinal" => "2029" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21654697" "web" => "Medline" ] ] ] ] ] ] ] ] 16 => array:3 [ "identificador" => "bib0085" "etiqueta" => "17" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Sea-level assessment of dynamic cerebral autoregulation predicts susceptibility to acute mountain sickness at high altitude" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "N.J. Cochand" 1 => "M. Wild" 2 => "J.V. Brugniaux" 3 => "P.J. Davies" 4 => "K.A. Evans" 5 => "R.G. Wise" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1161/STROKEAHA.111.621714" "Revista" => array:6 [ "tituloSerie" => "Stroke" "fecha" => "2011" "volumen" => "42" "paginaInicial" => "3628" "paginaFinal" => "3630" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21960569" "web" => "Medline" ] ] ] ] ] ] ] ] 17 => array:3 [ "identificador" => "bib0090" "etiqueta" => "18" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High altitude headache. Lessons from headaches at sea level" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "M. Sanchez del Rio" 1 => "M.A. Moskowitz" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Adv Exp Med Biol" "fecha" => "1999" "volumen" => "474" "paginaInicial" => "145" "paginaFinal" => "153" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/10634999" "web" => "Medline" ] ] ] ] ] ] ] ] 18 => array:3 [ "identificador" => "bib0095" "etiqueta" => "19" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High-altitude headache" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "L.P. Queiroz" 1 => "A.M. Rapoport" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Curr Pain Headache Rep" "fecha" => "2007" "volumen" => "11" "paginaInicial" => "293" "paginaFinal" => "296" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17686393" "web" => "Medline" ] ] ] ] ] ] ] ] 19 => array:3 [ "identificador" => "bib0100" "etiqueta" => "20" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Acute mountain sickness and ascent rates in trekkers above 2500m in the Nepali Himalaya" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "J. Vardy" 1 => "K. Judge" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Aviat Space Environ Med" "fecha" => "2006" "volumen" => "77" "paginaInicial" => "742" "paginaFinal" => "744" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16856361" "web" => "Medline" ] ] ] ] ] ] ] ] 20 => array:3 [ "identificador" => "bib0105" "etiqueta" => "21" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Medicine at high altitude" "autores" => array:1 [ 0 => array:3 [ "colaboracion" => "Birmingham Medical Research Expeditionary Society" "etal" => false "autores" => array:1 [ 0 => "A.D. Wright" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Clin Med" "fecha" => "2006" "volumen" => "6" "paginaInicial" => "604" "paginaFinal" => "608" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17228562" "web" => "Medline" ] ] ] ] ] ] ] ] 21 => array:3 [ "identificador" => "bib0110" "etiqueta" => "22" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High altitude arrhythmias" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "D.R. Woods" 1 => "S. Allen" 2 => "T.R. Betts" 3 => "D. Gardiner" 4 => "H. Montgomery" 5 => "J.M. Morgan" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1159/000127445" "Revista" => array:6 [ "tituloSerie" => "Cardiology" "fecha" => "2008" "volumen" => "111" "paginaInicial" => "239" "paginaFinal" => "246" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18434732" "web" => "Medline" ] ] ] ] ] ] ] ] 22 => array:3 [ "identificador" => "bib0115" "etiqueta" => "23" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Genetic variation in hypoxia inducible factor 1alpha and its possible association with high altitude adaptation in Sherpas" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "K. Suzuki" 1 => "T. Kizaki" 2 => "Y. Hitomi" 3 => "M. Nukita" 4 => "K. Kimoto" 5 => "N. Miyazawa" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Med Hypotheses" "fecha" => "2003" "volumen" => "61" "paginaInicial" => "385" "paginaFinal" => "389" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12944107" "web" => "Medline" ] ] ] ] ] ] ] ] 23 => array:3 [ "identificador" => "bib0120" "etiqueta" => "24" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Acute mountain sickness: medical problems associated with acute and subacute exposure to hypobaric hypoxia" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "C. Clarke" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1136/pgmj.2006.047662" "Revista" => array:6 [ "tituloSerie" => "Postgrad Med J" "fecha" => "2006" "volumen" => "82" "paginaInicial" => "748" "paginaFinal" => "753" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17099095" "web" => "Medline" ] ] ] ] ] ] ] ] 24 => array:3 [ "identificador" => "bib0125" "etiqueta" => "25" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Hypoxia-inducible factor-1 mediates activation of cultured vascular endothelial cells by inducing multiple angiogenic factors" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "M. Yamakawa" 1 => "L.X. Liu" 2 => "T. Date" 3 => "A.J. Belanger" 4 => "K.A. Vincent" 5 => "G.Y. Akita" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1161/01.RES.0000093984.48643.D7" "Revista" => array:6 [ "tituloSerie" => "Circ Res" "fecha" => "2003" "volumen" => "93" "paginaInicial" => "664" "paginaFinal" => "673" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12958144" "web" => "Medline" ] ] ] ] ] ] ] ] 25 => array:3 [ "identificador" => "bib0130" "etiqueta" => "26" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Hypothesis: angiogenesis cytokines in high altitude cerebral oedema" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:1 [ 0 => "J.W. Severinghaus" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Acta Anaesthesiol Scand Suppl" "fecha" => "1995" "volumen" => "107" "paginaInicial" => "177" "paginaFinal" => "178" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/8599273" "web" => "Medline" ] ] ] ] ] ] ] ] 26 => array:3 [ "identificador" => "bib0135" "etiqueta" => "27" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The Lake Louise Acute Mountain Sickness scoring system" "autores" => array:1 [ 0 => array:3 [ "colaboracion" => "The Lake Louise AMS Scoring Consensus Committee" "etal" => false "autores" => array:4 [ 0 => "R.C. Roach" 1 => "P. Bartsch" 2 => "P.H. Hackett" 3 => "O. Oelz" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:4 [ "titulo" => "Hypoxia and molecular medicine" "paginaInicial" => "273" "paginaFinal" => "274" "serieFecha" => "1993" ] ] ] ] ] ] 27 => array:3 [ "identificador" => "bib0140" "etiqueta" => "28" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Comparing questionnaires for the assessment of acute mountain sickness" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "P. Dellasanta" 1 => "S. Gaillard" 2 => "L. Loutan" 3 => "B. Kayser" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/ham.2007.8305" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2007" "volumen" => "8" "paginaInicial" => "184" "paginaFinal" => "191" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17824818" "web" => "Medline" ] ] ] ] ] ] ] ] 28 => array:3 [ "identificador" => "bib0145" "etiqueta" => "29" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Propiedades métricas de la versión española del Cuestionario de Mal de Altura del Lago Louise" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "F.J. Carod-Artal" 1 => "D. Ezpeleta Echávarri" 2 => "A.L. Guerrero Peral" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/j.nrl.2010.12.014" "Revista" => array:6 [ "tituloSerie" => "Neurología" "fecha" => "2011" "volumen" => "26" "paginaInicial" => "337" "paginaFinal" => "342" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21354668" "web" => "Medline" ] ] ] ] ] ] ] ] 29 => array:3 [ "identificador" => "bib0150" "etiqueta" => "30" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The environmental symptoms questionnaire: revisions and new field data" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "J.B. Sampson" 1 => "J.L. Kobrick" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Aviat Space Environ Med" "fecha" => "1980" "volumen" => "51" "paginaInicial" => "872" "paginaFinal" => "877" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/7417157" "web" => "Medline" ] ] ] ] ] ] ] ] 30 => array:3 [ "identificador" => "bib0155" "etiqueta" => "31" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Who should not go high: chronic disease and work at altitude during construction of the Qinghai-Tibet railroad" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "T.Y. Wu" 1 => "S.Q. Ding" 2 => "J.L. Liu" 3 => "M.T. Yu" 4 => "J.H. Jia" 5 => "Z.C. Chai" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/ham.2007.1015" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2007" "volumen" => "8" "paginaInicial" => "88" "paginaFinal" => "107" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17584003" "web" => "Medline" ] ] ] ] ] ] ] ] 31 => array:3 [ "identificador" => "bib0160" "etiqueta" => "32" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Incidence of high altitude illnesses among unacclimatized persons who acutely ascended to Tibet" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "Y. Ren" 1 => "Z. Fu" 2 => "W. Shen" 3 => "P. Jiang" 4 => "Y. He" 5 => "S. Peng" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/ham.2009.1049" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2010" "volumen" => "11" "paginaInicial" => "39" "paginaFinal" => "42" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/20367487" "web" => "Medline" ] ] ] ] ] ] ] ] 32 => array:3 [ "identificador" => "bib0165" "etiqueta" => "33" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Altitude illness: risk factors, prevention, presentation, and treatment" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "D.C. Fiore" 1 => "S. Hall" 2 => "P. Shoja" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Am Fam Physician" "fecha" => "2010" "volumen" => "82" "paginaInicial" => "1103" "paginaFinal" => "1110" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21121556" "web" => "Medline" ] ] ] ] ] ] ] ] 33 => array:3 [ "identificador" => "bib0170" "etiqueta" => "34" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High altitude cerebral edema" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:2 [ 0 => "P.H. Hackett" 1 => "R.C. Roach" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/1527029041352054" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2004" "volumen" => "5" "paginaInicial" => "136" "paginaFinal" => "146" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15265335" "web" => "Medline" ] ] ] ] ] ] ] ] 34 => array:3 [ "identificador" => "bib0175" "etiqueta" => "35" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Magnetic resonance imaging evidence of cytotoxic cerebral edema in acute sickness" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "K. Kallenberg" 1 => "D.M. Bailey" 2 => "S. Christ" 3 => "A. Mohr" 4 => "R. Roukens" 5 => "E. Menold" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1038/sj.jcbfm.9600404" "Revista" => array:6 [ "tituloSerie" => "J Cereb Blood Flow Metab" "fecha" => "2007" "volumen" => "27" "paginaInicial" => "1064" "paginaFinal" => "1071" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17024110" "web" => "Medline" ] ] ] ] ] ] ] ] 35 => array:3 [ "identificador" => "bib0180" "etiqueta" => "36" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High-altitude cerebral edema evaluated with magnetic resonance imaging: clinical correlation and pathophysiology" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "P.H. Hackett" 1 => "P.R. Yarnell" 2 => "R. Hill" 3 => "K. Reynard" 4 => "J. Heit" 5 => "J. McCormick" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J Am Med Assoc" "fecha" => "1998" "volumen" => "280" "paginaInicial" => "1920" "paginaFinal" => "1925" ] ] ] ] ] ] 36 => array:3 [ "identificador" => "bib0185" "etiqueta" => "37" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Microhemorrhages in nonfatal high-altitude cerebral edema" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "K. Kallenberg" 1 => "C. Dehnert" 2 => "A. Dorfler" 3 => "P.D. Schellinger" 4 => "D.M. Bailey" 5 => "M. Knauth" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1038/jcbfm.2008.55" "Revista" => array:6 [ "tituloSerie" => "J Cereb Blood Flow Metab" "fecha" => "2008" "volumen" => "28" "paginaInicial" => "1635" "paginaFinal" => "1642" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18523438" "web" => "Medline" ] ] ] ] ] ] ] ] 37 => array:3 [ "identificador" => "bib0190" "etiqueta" => "38" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The headache of high altitude and microgravity – similarities with clinical syndromes of cerebral venous hypertension" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "M.H. Wilson" 1 => "C.H. Imray" 2 => "A.R. 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Gertsch" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/1527029041352126" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2004" "volumen" => "5" "paginaInicial" => "171" "paginaFinal" => "179" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15265338" "web" => "Medline" ] ] ] ] ] ] ] ] 39 => array:3 [ "identificador" => "bib0200" "etiqueta" => "40" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Cerebral thrombosis at altitude: its pathogenesis and the problems of prevention and treatment" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "S.Y. Song" 1 => "T. Asaji" 2 => "Y. Tanizaki" 3 => "T. Fujimaki" 4 => "M. Matsutani" 5 => "R. Okeda" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Aviat Space Environ Med" "fecha" => "1986" "volumen" => "57" "paginaInicial" => "71" "paginaFinal" => "76" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/3942573" "web" => "Medline" ] ] ] ] ] ] ] ] 40 => array:3 [ "identificador" => "bib0205" "etiqueta" => "41" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Altitude-related deaths in seven trekkers in the Himalayas" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "J. Dickinson" 1 => "D. Health" 2 => "J. Gosney" 3 => "D. Williams" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Thorax" "fecha" => "1983" "volumen" => "38" "paginaInicial" => "646" "paginaFinal" => "656" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/6623417" "web" => "Medline" ] ] ] ] ] ] ] ] 41 => array:3 [ "identificador" => "bib0210" "etiqueta" => "42" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Verbal free recall in high altitude: proper names vs common names" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "G. Pelamatti" 1 => "M. Pascotto" 2 => "C. Semenza" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Cortex" "fecha" => "2003" "volumen" => "39" "paginaInicial" => "97" "paginaFinal" => "103" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12627756" "web" => "Medline" ] ] ] ] ] ] ] ] 42 => array:3 [ "identificador" => "bib0215" "etiqueta" => "43" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Cognition and metacognition at extreme altitudes on Mount Everest" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "T.O. Nelson" 1 => "J. Dunlosky" 2 => "D.M. White" 3 => "J. Steinberg" 4 => "B.D. Townes" 5 => "D. Anderson" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "J Exp Psychol Gen" "fecha" => "1990" "volumen" => "119" "paginaInicial" => "367" "paginaFinal" => "374" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/2148573" "web" => "Medline" ] ] ] ] ] ] ] ] 43 => array:3 [ "identificador" => "bib0220" "etiqueta" => "44" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High altitude headache: efficacy of acetaminophen vs. ibuprofen in a randomized, controlled trial" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "N.S. Harris" 1 => "R.P. Wenzel" 2 => "S.H. Thomas" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "J Emerg Med" "fecha" => "2003" "volumen" => "24" "paginaInicial" => "383" "paginaFinal" => "387" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12745039" "web" => "Medline" ] ] ] ] ] ] ] ] 44 => array:3 [ "identificador" => "bib0225" "etiqueta" => "45" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Acetazolamide in the treatment of acute mountain sickness: clinical efficacy and effect on gas exchange" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "C.K. Grissom" 1 => "R.C. Roach" 2 => "F.H. Sarnquist" 3 => "P.H. Hackett" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Ann Intern Med" "fecha" => "1992" "volumen" => "116" "paginaInicial" => "461" "paginaFinal" => "465" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/1739236" "web" => "Medline" ] ] ] ] ] ] ] ] 45 => array:3 [ "identificador" => "bib0230" "etiqueta" => "46" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Dexamethasone for prevention and treatment of acute mountain sickness" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "P.H. Hackett" 1 => "R.C. Roach" 2 => "R.A. Wood" 3 => "R.G. Foutch" 4 => "R.T. Meehan" 5 => "D. Rennie" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Aviat Space Environ Med" "fecha" => "1988" "volumen" => "59" "paginaInicial" => "950" "paginaFinal" => "954" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/3190622" "web" => "Medline" ] ] ] ] ] ] ] ] 46 => array:3 [ "identificador" => "bib0235" "etiqueta" => "47" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Treatment of acute mountain sickness by simulated descent: a randomised controlled trial" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "P. Bärtsch" 1 => "B. Merki" 2 => "D. Hofstetter" 3 => "M. Maggiorini" 4 => "B. Kayser" 5 => "O. Oelz" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Br Med J" "fecha" => "1993" "volumen" => "306" "paginaInicial" => "1098" "paginaFinal" => "1101" ] ] ] ] ] ] 47 => array:3 [ "identificador" => "bib0240" "etiqueta" => "48" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "High hopes at high altitudes: pharmacotherapy for acute mountain sickness and high-altitude cerebral and pulmonary oedema" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "A. Wright" 1 => "S. Brearey" 2 => "C. Imray" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1517/14656566.9.1.119" "Revista" => array:7 [ "tituloSerie" => "Expert Opin Pharmacother" "fecha" => "2008" "volumen" => "9" "paginaInicial" => "119" "paginaFinal" => "127" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18076343" "web" => "Medline" ] ] "itemHostRev" => array:3 [ "pii" => "S1873994611002510" "estado" => "S300" "issn" => "18739946" ] ] ] ] ] ] ] 48 => array:3 [ "identificador" => "bib0245" "etiqueta" => "49" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Hypoxia-induced vascular endothelial growth factor expression causes vascular leakage in the brain" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "H.J. Schoch" 1 => "S. Fischer" 2 => "H.H. Marti" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:6 [ "tituloSerie" => "Brain" "fecha" => "2002" "volumen" => "125" "paginaInicial" => "2549" "paginaFinal" => "2557" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12390979" "web" => "Medline" ] ] ] ] ] ] ] ] 49 => array:3 [ "identificador" => "bib0250" "etiqueta" => "50" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Prospective, double-blind, randomized, placebo-controlled comparison of acetazolamide versus ibuprofen for prophylaxis against high altitude headache: the Headache Evaluation at Altitude Trial (HEAT)" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "J.H. Gertsch" 1 => "G.S. Lipman" 2 => "P.S. Holck" 3 => "A. Merritt" 4 => "A. Mulcahy" 5 => "R.S. Fisher" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/j.wem.2010.06.009" "Revista" => array:6 [ "tituloSerie" => "Wilderness Environ Med" "fecha" => "2010" "volumen" => "21" "paginaInicial" => "236" "paginaFinal" => "243" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/20832701" "web" => "Medline" ] ] ] ] ] ] ] ] 50 => array:3 [ "identificador" => "bib0255" "etiqueta" => "51" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Efficacy and harm of pharmacological prevention of acute mountain sickness: quantitative systematic review" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "L. Dumont" 1 => "C. Mardirosoff" 2 => "M.R. Tramèr" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Br Med J" "fecha" => "2000" "volumen" => "321" "paginaInicial" => "267" "paginaFinal" => "277" ] ] ] ] ] ] 51 => array:3 [ "identificador" => "bib0260" "etiqueta" => "52" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Acetazolamide 125mg BD is not significantly different from 375mg BD in the prevention of acute mountain sickness: the prophylactic acetazolamide dosage comparison for efficacy (PACE) trial" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "B. Basnyat" 1 => "J.H. Gertsch" 2 => "P.S. Holck" 3 => "E.W. Johnson" 4 => "A.M. Luks" 5 => "B.P. Donham" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1089/ham.2006.7.17" "Revista" => array:6 [ "tituloSerie" => "High Alt Med Biol" "fecha" => "2006" "volumen" => "7" "paginaInicial" => "17" "paginaFinal" => "27" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16544963" "web" => "Medline" ] ] ] ] ] ] ] ] 52 => array:3 [ "identificador" => "bib0265" "etiqueta" => "53" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Spironolactone does not prevent acute mountain sickness: a prospective, double-blind, randomized, placebo-controlled trial by SPACE Trial Group (spironolactone and acetazolamide trial in the prevention of acute mountain sickness group)" "autores" => array:1 [ 0 => array:3 [ "colaboracion" => "SPACE Trial Group" "etal" => true "autores" => array:6 [ 0 => "B. Basnyat" 1 => "P.S. Holck" 2 => "M. Pun" 3 => "S. Halverson" 4 => "P. Szawarski" 5 => "J. Gertsch" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/j.wem.2010.10.009" "Revista" => array:6 [ "tituloSerie" => "Wilderness Environ Med" "fecha" => "2011" "volumen" => "22" "paginaInicial" => "15" "paginaFinal" => "22" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21377114" "web" => "Medline" ] ] ] ] ] ] ] ] 53 => array:3 [ "identificador" => "bib0270" "etiqueta" => "54" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Prevention of acute mountain sickness by dexamethasone" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "T.S. Johnson" 1 => "P.B. Rock" 2 => "C.S. Fulco" 3 => "L.A. Trad" 4 => "R.F. Spark" 5 => "J.T. Maher" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1056/NEJM198403153101103" "Revista" => array:6 [ "tituloSerie" => "N Engl J Med" "fecha" => "1984" "volumen" => "310" "paginaInicial" => "683" "paginaFinal" => "686" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/6700643" "web" => "Medline" ] ] ] ] ] ] ] ] 54 => array:3 [ "identificador" => "bib0275" "etiqueta" => "55" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Glucocorticoids as prophylaxis against acute mountain sickness" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "M. Basu" 1 => "R.C. Sawhney" 2 => "S. Kumar" 3 => "K. Pal" 4 => "R. Prasad" 5 => "W. Selvamurthy" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Clin Endocrinol" "fecha" => "2002" "volumen" => "57" "paginaInicial" => "761" "paginaFinal" => "767" ] ] ] ] ] ] 55 => array:3 [ "identificador" => "bib0280" "etiqueta" => "56" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Randomised, double blind, placebo controlled comparison of ginkgo biloba and acetazolamide for prevention of acute mountain sickness among Himalayan trekkers: the prevention of high altitude illness trial (PHAIT)" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:5 [ 0 => "J.H. Gertsch" 1 => "B. Basnyat" 2 => "E.W. Johnson" 3 => "J. Onopa" 4 => "P.S. Holck" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:4 [ "tituloSerie" => "Br Med J" "fecha" => "2004" "volumen" => "328" "paginaInicial" => "797" ] ] ] ] ] ] 56 => array:3 [ "identificador" => "bib0285" "etiqueta" => "57" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Aspirin for prophylaxis against headache at high altitudes: randomised, double blind, placebo controlled trial" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "M. Burtscher" 1 => "R. Likar" 2 => "W. Nachbauer" 3 => "M. Philadelphy" ] ] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Br Med J" "fecha" => "1998" "volumen" => "316" "paginaInicial" => "1057" "paginaFinal" => "1058" ] ] ] ] ] ] 57 => array:3 [ "identificador" => "bib0290" "etiqueta" => "58" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Sumatriptan for prevention of acute mountain sickness: randomized clinical trial" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:4 [ 0 => "S. Jafarian" 1 => "F. Gorouhi" 2 => "S. Salimi" 3 => "J. Lotfi" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1002/ana.21162" "Revista" => array:6 [ "tituloSerie" => "Ann Neurol" "fecha" => "2007" "volumen" => "62" "paginaInicial" => "273" "paginaFinal" => "277" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17557349" "web" => "Medline" ] ] ] ] ] ] ] ] 58 => array:3 [ "identificador" => "bib0295" "etiqueta" => "59" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Low-dose theophylline reduces symptoms of acute mountain sickness" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:6 [ 0 => "T.E. Küpper" 1 => "K.P. Strohl" 2 => "M. Hoefer" 3 => "U. Gieseler" 4 => "C.M. Netzer" 5 => "N.C. Netzer" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1111/j.1708-8305.2008.00228.x" "Revista" => array:6 [ "tituloSerie" => "J Travel Med" "fecha" => "2008" "volumen" => "15" "paginaInicial" => "307" "paginaFinal" => "314" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/19006503" "web" => "Medline" ] ] ] ] ] ] ] ] ] ] ] ] ] "idiomaDefecto" => "en" "url" => "/21735808/0000002900000009/v1_201411150342/S2173580814001321/v1_201411150342/en/main.assets" "Apartado" => array:4 [ "identificador" => "9423" "tipo" => "SECCION" "en" => array:2 [ "titulo" => "Review articles" "idiomaDefecto" => true ] "idiomaDefecto" => "en" ] "PDF" => "https://static.elsevier.es/multimedia/21735808/0000002900000009/v1_201411150342/S2173580814001321/v1_201411150342/en/main.pdf?idApp=UINPBA00004N&text.app=https://www.elsevier.es/" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S2173580814001321?idApp=UINPBA00004N"]

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Cefalea de elevada altitud y mal de altura

F.J. Carod-Artal

Servicio de Neurología, Hospital Virgen de la Luz, Cuenca, Spain

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    "textoCompleto" => "<span class="elsevierStyleSections"><span id="sec0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0055">Introduction</span><p id="par0005" class="elsevierStylePara elsevierViewall">The first written record about high-altitude headache dates back to 30 BCE and is owed to Too Kin&#44; an officer of the Imperial Chinese Army&#46; Too Kin&#44; along with his troops&#44; experienced an episode of altitude sickness in a mountain range in Afghanistan which he named the Great Headache Mountain and the Little Headache Mountain&#46;<a class="elsevierStyleCrossRef" href="#bib0005"><span class="elsevierStyleSup">1</span></a> Two millennia went by before Paul Bert&#44; the chair of physiology at the Sorbonne after Claude Bernard&#44; developed the modern discipline of altitude physiology&#46;<a class="elsevierStyleCrossRef" href="#bib0010"><span class="elsevierStyleSup">2</span></a> In 1913&#44; Thomas Ravenhill provided the first clinical descriptions of signs and symptoms associated with rapid ascent to high altitude in the north of Chile&#44; and reported on both high-altitude cerebral oedema and high-altitude pulmonary oedema&#46;<a class="elsevierStyleCrossRef" href="#bib0015"><span class="elsevierStyleSup">3</span></a></p><p id="par0010" class="elsevierStylePara elsevierViewall">Headache is the most common complication of exposure to high altitude&#44; and it can appear as isolated high-altitude headache &#40;HAH&#41; or in conjunction with acute mountain sickness &#40;AMS&#41;&#46; HAH is a global health problem whose incidence has increased over the past decades due to different factors&#46; These include more opportunities for travel&#44; exercise&#44; and tourism which therefore expose thousands of tourists&#44; travellers and sports enthusiasts to a rapid increase in altitude&#44; frequently with no previous acclimation&#46;<a class="elsevierStyleCrossRef" href="#bib0020"><span class="elsevierStyleSup">4</span></a> Exposure to altitude is considered high for subjects at elevations of 1500 to 3700<span class="elsevierStyleHsp" style=""></span>m above sea level&#44; very high at 3700 to 5500<span class="elsevierStyleHsp" style=""></span>m&#44; and extreme above 5500<span class="elsevierStyleHsp" style=""></span>m&#46;<a class="elsevierStyleCrossRef" href="#bib0025"><span class="elsevierStyleSup">5</span></a></p><p id="par0015" class="elsevierStylePara elsevierViewall">However&#44; a person with high altitude exposure can experience different types of headaches in addition to headache associated with altitude&#46; This being the case&#44; episodic migraine crises precipitated by hypoxia and altitude&#44; as well as headache linked to acute mountain sickness&#44; must be considered&#46; The purpose of this article is to review several aspects related to diagnosis and treatment of HAH and AMS&#46; To this end&#44; we searched the Medline database for all articles published in English or Spanish up to February 2012&#44; using the keywords &#8216;headache altitude&#8217; and &#8216;acute mountain sickness&#8217;&#46;</p></span><span id="sec0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0060">High-altitude headache</span><span id="sec0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0065">Epidemiology</span><p id="par0020" class="elsevierStylePara elsevierViewall">It is estimated that at least 25&#37; of non-acclimated individuals exposed to altitudes of 1859 to 2750<span class="elsevierStyleHsp" style=""></span>m experience high-altitude headache&#46; At altitudes above 3000<span class="elsevierStyleHsp" style=""></span>m&#44; 80&#37; of individuals will have HAH and almost 100&#37; will experience headache at 4500<span class="elsevierStyleHsp" style=""></span>m or higher&#46;<a class="elsevierStyleCrossRef" href="#bib0020"><span class="elsevierStyleSup">4</span></a></p></span><span id="sec0020" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0070">Definition&#44; clinical presentation and risk factors</span><p id="par0025" class="elsevierStylePara elsevierViewall">The second edition of the International Classification of Headache Disorders &#40;ICHD-II&#41;<a class="elsevierStyleCrossRef" href="#bib0030"><span class="elsevierStyleSup">6</span></a> includes high-altitude headache &#40;subsection 10&#46;1&#46;1&#41; in chapter 10 &#40;Headache attributed to disorder of homoeostasis&#41;&#44; section 10&#46;1 &#40;Headache attributed to hypoxia and&#47;or hypercapnia&#41;&#46; Diagnostic criteria are listed in <a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>&#46;</p><elsevierMultimedia ident="tbl0005"></elsevierMultimedia><p id="par0030" class="elsevierStylePara elsevierViewall">HAH can appear as an isolated symptom within the first 24<span class="elsevierStyleHsp" style=""></span>hours of exposure to altitudes above 2500<span class="elsevierStyleHsp" style=""></span>m without previous acclimation&#44; or it may present along with more varied signs and symptoms which constitute AMS&#44; as we will discuss in a later section&#46;<a class="elsevierStyleCrossRef" href="#bib0035"><span class="elsevierStyleSup">7</span></a></p><p id="par0035" class="elsevierStylePara elsevierViewall">HAH has a mild to moderate intensity and can be described as bilateral dull or pressing pain in the frontal&#44; frontoparietal&#44; or holocranial regions&#46;<a class="elsevierStyleCrossRefs" href="#bib0040"><span class="elsevierStyleSup">8&#44;9</span></a> Clinically&#44; this headache is usually aggravated by exertion and head or body movement&#46; It may also present with throbbing pain which&#44; according to different studies&#44; affects 30&#37;<a class="elsevierStyleCrossRef" href="#bib0040"><span class="elsevierStyleSup">8</span></a> to 75&#37;<a class="elsevierStyleCrossRef" href="#bib0045"><span class="elsevierStyleSup">9</span></a> of individuals&#46; Headaches either begin upon awakening&#44; or wake subjects at night&#44; in at least 25&#37; of the cases&#46; This type of headache seems to be more intense in women and in individuals with a history of other types of headache in daily life&#46;<a class="elsevierStyleCrossRef" href="#bib0040"><span class="elsevierStyleSup">8</span></a></p><p id="par0040" class="elsevierStylePara elsevierViewall">The connection between HAH and episodic migraine is yet to be determined&#46; As pain in HAH seems to be more intense in patients with a previous history of migraine&#44; some authors hypothesise that it may be associated with migraine&#46;<a class="elsevierStyleCrossRef" href="#bib0040"><span class="elsevierStyleSup">8</span></a> Migraine without aura should be differentiated from HAH&#44; especially in subjects with a prior history of migraine&#46; It is believed that some cases of migraine with aura could be related to the presence of right-to-left shunt blood vessels that are increasingly active with physical exertion and altitude&#46;<a class="elsevierStyleCrossRef" href="#bib0050"><span class="elsevierStyleSup">10</span></a> Doctors have also described isolated cases of primary cluster headache triggered by exposure to high altitude and responding to oxygen therapy&#46;<a class="elsevierStyleCrossRef" href="#bib0055"><span class="elsevierStyleSup">11</span></a></p><p id="par0045" class="elsevierStylePara elsevierViewall">Rapid ascent to a high altitude is the main risk factor&#46;<a class="elsevierStyleCrossRefs" href="#bib0035"><span class="elsevierStyleSup">7&#44;12&#8211;14</span></a> Known risk factors for HAH are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>&#46; According to a study comprising 506 mountaineers who experienced headache at altitudes of 2200 to 3817<span class="elsevierStyleHsp" style=""></span>m&#44; risk factors for HAH were previous history of migraine&#44; intense physical exertion&#44; and low arterial oxygen saturation&#46;<a class="elsevierStyleCrossRef" href="#bib0070"><span class="elsevierStyleSup">14</span></a> Adults and the elderly have a lower incidence of headache than the younger population&#44; which may be due to the effect of cerebral atrophy&#46; A good level of physical fitness &#40;&#8216;being fit&#8217;&#41; does not prevent HAH&#46;</p><elsevierMultimedia ident="tbl0010"></elsevierMultimedia></span><span id="sec0025" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0075">Pathogenesis</span><p id="par0050" class="elsevierStylePara elsevierViewall">There is an inverse relationship between altitude&#47;atmospheric pressure and PaO<span class="elsevierStyleInf">2</span>&#46; Chemoreceptors in the carotid body of a person gaining altitude detect a reduction in PaO<span class="elsevierStyleInf">2</span>&#46; Hypoxia promotes a neurohumoral and haemodynamic response that gives rise to increased capillary pressure and vascular and cerebral oedema&#46; Hypoxia-induced cerebral vasodilation is a probable cause of headache&#46; Cerebral blood flow is elevated in the hypoxic state and returns to pre-ascent values with acclimation&#46;<a class="elsevierStyleCrossRef" href="#bib0035"><span class="elsevierStyleSup">7</span></a></p><p id="par0055" class="elsevierStylePara elsevierViewall">Cerebral autoregulation&#44; a process aimed at regulating cerebral perfusion according to variations in blood pressure&#44; is altered by hypoxia and in individuals suffering from HAH and AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0075"><span class="elsevierStyleSup">15</span></a> Studies performed with transcranial Doppler&#44; which measures velocity in the middle cerebral artery &#40;MCA&#41; as an indicator of cerebral blood flow&#44; show considerable variations in flow velocity&#46;<a class="elsevierStyleCrossRef" href="#bib0080"><span class="elsevierStyleSup">16</span></a> Sea-level assessment of dynamic cerebral autoregulation&#44; which uses transcranial Doppler to calculate velocity in the MCA&#44; can act as a predictor for susceptibility to AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0085"><span class="elsevierStyleSup">17</span></a> A lower baseline autoregulation index may be considered a potential risk factor for AMS&#46;</p><p id="par0060" class="elsevierStylePara elsevierViewall">However&#44; researchers have also proposed other factors apart from hypobaric hypoxia that favour HAH&#44; for example&#44; alterations in the blood-brain barrier promoted by different mediators&#44; such as vascular endothelial growth factor&#44; nitric oxide&#44; or bradykinin&#46;<a class="elsevierStyleCrossRef" href="#bib0020"><span class="elsevierStyleSup">4</span></a> Some also suggest that the trigeminovascular system may be activated at high altitude by either chemical stimuli &#40;nitric oxide&#41; or mechanical stimuli &#40;vasodilation&#41;&#46;<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">18</span></a></p></span><span id="sec0030" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0080">Diagnosis</span><p id="par0065" class="elsevierStylePara elsevierViewall">For HAH to be diagnosed&#44; the condition must appear at altitudes above 2500<span class="elsevierStyleHsp" style=""></span>m and it may not be attributable to other causes&#46; For this reason&#44; differential diagnosis for HAH must consider an array of toxic and metabolic causes and space-occupying cerebral lesions listed in <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>&#46; The differential diagnosis commonly includes headache due to viral infections and dehydration&#46;<a class="elsevierStyleCrossRef" href="#bib0095"><span class="elsevierStyleSup">19</span></a></p><elsevierMultimedia ident="tbl0015"></elsevierMultimedia></span></span><span id="sec0035" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0085">Acute mountain sickness</span><span id="sec0040" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0090">Epidemiology</span><p id="par0070" class="elsevierStylePara elsevierViewall">Incidence of AMS is approximately 45&#37; to 95&#37;&#44; depending on the series&#46; It is estimated that almost 50&#37; of trekkers ascending above 5000<span class="elsevierStyleHsp" style=""></span>m experience acute mountain sickness&#46;<a class="elsevierStyleCrossRef" href="#bib0100"><span class="elsevierStyleSup">20</span></a></p></span><span id="sec0045" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0095">Acclimation</span><p id="par0075" class="elsevierStylePara elsevierViewall">Immediate physiological changes induced by hypoxia and altitude include increases in heart and respiratory rates&#44; increased diuresis&#44; alterations in taste perception&#44; nasal congestion&#44; and sometimes syncope&#46; Acclimation can be considered the final stage of a process in which individuals adapt to altitude hypoxia&#46; While acclimation takes several days to weeks&#44; symptoms of AMS present at the onset of this process&#46;<a class="elsevierStyleCrossRef" href="#bib0035"><span class="elsevierStyleSup">7</span></a></p></span><span id="sec0050" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0100">Symptoms</span><p id="par0080" class="elsevierStylePara elsevierViewall">The main symptom of AMS is headache&#44; frequently accompanied by sleep disorders&#44; fatigue&#44; dizziness and instability&#44; nausea&#44; and anorexia&#46; Insomnia is the second most frequent symptom and presents in at least 60&#37; of all individuals reaching 3500<span class="elsevierStyleHsp" style=""></span>m&#46; Non-restorative sleep may be secondary to periodic breathing that interrupts sleep architecture with a pattern of hypoxia-hyperventilation-hypocapnia&#59; other factors such as headache and fatigue may also promote insomnia&#46;<a class="elsevierStyleCrossRef" href="#bib0105"><span class="elsevierStyleSup">21</span></a> High-altitude syncope seems to be a vasovagal phenomenon related to hypoxia&#44; although at times the presence of arrhythmias may trigger it&#46;<a class="elsevierStyleCrossRef" href="#bib0110"><span class="elsevierStyleSup">22</span></a></p><p id="par0085" class="elsevierStylePara elsevierViewall">The frequency and intensity of symptoms associated with AMS seem to point to some degree of individual susceptibility and considerable inter-individual variability&#46; For this reason it is believed that there may be a certain genetic predisposition to AMS&#46; In any case&#44; human response to hypobaric hypoxia seems to be polygenic<a class="elsevierStyleCrossRef" href="#bib0115"><span class="elsevierStyleSup">23</span></a> and determined by different expression of genes encoding different proteins&#44; such as serum erythropoietin&#44; hypoxia-inducible factor 1alpha &#40;HIF-1alpha&#41;&#44; angiotensin-converting enzyme&#44; aldosterone&#44; and nitric oxide synthase activity&#44; among others&#46;<a class="elsevierStyleCrossRef" href="#bib0020"><span class="elsevierStyleSup">4</span></a></p></span><span id="sec0055" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0105">Pathophysiology</span><p id="par0090" class="elsevierStylePara elsevierViewall">From a pathophysiological point of view&#44; the main pathogenetic factor in acute mountain sickness is hypobaric hypoxia&#44; which can be exacerbated by hypoventilation&#44; a periodic breathing pattern&#44; and relatively intense physical exertion&#46; The combination of these factors leads to an increase in capillary permeability&#44; sodium retention&#44; vasodilation&#44; and an increase in cerebral blood flow and pulmonary hypertension&#46;<a class="elsevierStyleCrossRef" href="#bib0120"><span class="elsevierStyleSup">24</span></a></p><p id="par0095" class="elsevierStylePara elsevierViewall">Apart from O<span class="elsevierStyleInf">2</span> and CO<span class="elsevierStyleInf">2</span> concentrations&#44; several factors can affect blood vessel tonicity in hypoxia&#44; mainly cerebral adenosine&#44; potassium ion&#44; and nitric oxide synthase levels&#46; Vascular permeability may be influenced not only by hypoxia but also by different chemical mediators&#44; such as hypoxia-inducible factor 1 &#40;HIF-1&#41;<a class="elsevierStyleCrossRef" href="#bib0125"><span class="elsevierStyleSup">25</span></a> and vascular endothelial growth factor &#40;VEGF&#41;&#46;<a class="elsevierStyleCrossRef" href="#bib0130"><span class="elsevierStyleSup">26</span></a></p></span><span id="sec0060" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0110">Diagnosis</span><p id="par0100" class="elsevierStylePara elsevierViewall">The Lake Louise AMS scoring system was developed for establishing an early diagnosis and monitoring severity of AMS symptoms in individuals exposed to high altitudes&#46;<a class="elsevierStyleCrossRef" href="#bib0135"><span class="elsevierStyleSup">27</span></a> It consists of 2 sections&#44; a self-reported questionnaire and a clinical assessment form&#46; A diagnosis of AMS requires the presence of the main symptom&#44; headache &#40;even when it presents with mild intensity&#41;&#44; plus at least 1 additional symptom&#46;</p><p id="par0105" class="elsevierStylePara elsevierViewall">Diagnostic criteria for AMS by Lake Louise Consensus Group are listed in <a class="elsevierStyleCrossRef" href="#tbl0020">Table 4</a>&#46; Scores of 3 to 5 on the questionnaire indicate mild AMS and scores of 6 or more indicate severe AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0140"><span class="elsevierStyleSup">28</span></a> An adapted Spanish version of the Lake Louise AMS questionnaire was validated a few years ago&#46;<a class="elsevierStyleCrossRef" href="#bib0145"><span class="elsevierStyleSup">29</span></a> The Environmental Symptoms Questionnaire is a more detailed and time-consuming questionnaire that may be useful for assessing severity of AMS symptoms in applied research&#46;<a class="elsevierStyleCrossRef" href="#bib0150"><span class="elsevierStyleSup">30</span></a></p><elsevierMultimedia ident="tbl0020"></elsevierMultimedia></span></span><span id="sec0065" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0115">High-altitude cerebral oedema</span><span id="sec0070" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0120">Epidemiology</span><p id="par0110" class="elsevierStylePara elsevierViewall">High-altitude cerebral oedema &#40;HACE&#41; is the most severe form of AMS&#46; It may occur above 2500<span class="elsevierStyleHsp" style=""></span>m and should therefore be considered in differential diagnosis of HAH&#46; HACE is a potentially highly severe encephalopathy that may affect 0&#46;5&#37; to 1&#37; of all individuals suffering from AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0155"><span class="elsevierStyleSup">31</span></a> In addition&#44; it is estimated that 5&#37; of non-acclimated individuals may present cerebral oedema above 4500<span class="elsevierStyleHsp" style=""></span>m&#46; The incidence of high-altitude pulmonary oedema is approximately 2&#37;&#46;<a class="elsevierStyleCrossRef" href="#bib0160"><span class="elsevierStyleSup">32</span></a></p></span><span id="sec0075" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0125">Symptoms</span><p id="par0115" class="elsevierStylePara elsevierViewall">The mildest forms of cerebral oedema present with headache&#44; dizziness&#44; vertigo&#44; and reaction time retardation&#46; The most severe forms can present with ataxia&#44; altered level of consciousness&#44; hallucinations&#44; seizures&#44; stupor&#44; and coma&#46; Above 7500<span class="elsevierStyleHsp" style=""></span>m&#44; 32&#37; of climbers experience hallucinations&#46; An increase in intracranial pressure may lead to papilloedema&#44; retinal haemorrhage and paralysis of cranial nerves&#44; especially cranial nerve VI&#46; The most severe forms may progress to cerebral herniation&#44; and intracranial hypertension resulting in death&#46;<a class="elsevierStyleCrossRef" href="#bib0165"><span class="elsevierStyleSup">33</span></a> Retinal haemorrhages&#44; which are frequent during high-altitude ascent&#44; occur in 30&#37; and 50&#37; of individuals suffering from AMS and HACE&#44; respectively&#46;<a class="elsevierStyleCrossRef" href="#bib0170"><span class="elsevierStyleSup">34</span></a></p></span><span id="sec0080" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0130">Neuroimaging findings</span><p id="par0120" class="elsevierStylePara elsevierViewall">Neuroimaging studies &#40;cerebral computed tomography and brain magnetic resonance imaging&#41; showed small ventricles and cerebral sulci effacement in climbers suffering HACE&#46; It is not yet known whether cerebral oedema is of vasogenic or cytotoxic origin&#44; or whether one precedes the other or if both present simultaneously&#46;<a class="elsevierStyleCrossRef" href="#bib0035"><span class="elsevierStyleSup">7</span></a> Hypoxia may produce a generalised vasogenic oedema subsequent to an increase in blood-brain barrier permeability&#46; However&#44; both cytotoxic<a class="elsevierStyleCrossRef" href="#bib0175"><span class="elsevierStyleSup">35</span></a> and vasogenic<a class="elsevierStyleCrossRef" href="#bib0180"><span class="elsevierStyleSup">36</span></a> cellular oedema have been detected&#46; Cytotoxic oedema may derive from disorders in ATP-dependent sodium-potassium pump functioning&#46;</p><p id="par0125" class="elsevierStylePara elsevierViewall">Individuals suffering from high-altitude cerebral and pulmonary oedema showed hyperintense areas in the splenium of the corpus callosum and in the centrum semiovale&#44; but no abnormalities in cortical grey matter&#46;<a class="elsevierStyleCrossRef" href="#bib0120"><span class="elsevierStyleSup">24</span></a> On this basis&#44; many authors suggest that high-altitude cerebral oedema is predominantly a reversible vasogenic cerebral oedema in the white matter&#46;<a class="elsevierStyleCrossRef" href="#bib0180"><span class="elsevierStyleSup">36</span></a> Brain MRI has also shown hyperintensities in subcortical white matter in individuals above 7000<span class="elsevierStyleHsp" style=""></span>m&#46;<a class="elsevierStyleCrossRef" href="#bib0180"><span class="elsevierStyleSup">36</span></a></p><p id="par0130" class="elsevierStylePara elsevierViewall">Additional brain MRI studies in HACE patients revealed haemosiderin depositions&#44; mostly in the corpus callosum&#46;<a class="elsevierStyleCrossRef" href="#bib0185"><span class="elsevierStyleSup">37</span></a></p></span><span id="sec0085" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0135">Pathogenesis</span><p id="par0135" class="elsevierStylePara elsevierViewall">HACE pathogenesis has traditionally been based on the theory of intracranial hypertension secondary to hypobaric hypoxia&#46; However&#44; some authors have stated that correlation between headache in AMS and cerebral oedema is unclear&#46;<a class="elsevierStyleCrossRef" href="#bib0020"><span class="elsevierStyleSup">4</span></a> It has recently been suggested that hypoxia may affect not only cerebral blood flow&#44; but also cause a certain degree of cerebral venous insufficiency&#46; Thus&#44; a slight increase in central venous pressure &#40;as occurs with hypoxia-induced pulmonary vasoconstriction&#44; for example&#41; may compromise cerebral venous outflow at high altitudes and favour oedema&#46;<a class="elsevierStyleCrossRef" href="#bib0190"><span class="elsevierStyleSup">38</span></a> Cerebral oedema is considered the main factor leading to increased brain volume and intracranial hypertension&#46; However&#44; there are other mechanisms&#44; such as increases in cerebral blood flow or venous outflow obstruction&#44; which may also increase intracranial pressure&#46;</p></span></span><span id="sec0145" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0140">Other neurological and neuropsychological complications associated with high altitude</span><p id="par0210" class="elsevierStylePara elsevierViewall">Cerebrovascular complications described in association with high altitude include transient ischaemic attack and ischaemic stroke&#46; Their origin may be related to vasospasm and vasoconstriction phenomena favoured by the hypocapnia&#44; severe dehydration&#44; and thrombophilia associated with hypoxia&#46;<a class="elsevierStyleCrossRef" href="#bib0195"><span class="elsevierStyleSup">39</span></a> Some cases of patients who died at high altitude due to cerebral venous thrombosis can be found in medical literature&#46;<a class="elsevierStyleCrossRef" href="#bib0200"><span class="elsevierStyleSup">40</span></a> Histopathological and postmortem examinations have confirmed the presence of ring-shaped microhaemorrhages associated with cerebral venous thrombosis&#46;<a class="elsevierStyleCrossRefs" href="#bib0120"><span class="elsevierStyleSup">24&#44;40&#44;41</span></a></p><p id="par0145" class="elsevierStylePara elsevierViewall">Exposure to hypobaric hypoxia leads to neuropsychological disturbances in perception&#44; memory&#44; language&#44; reaction time&#44; learning&#44; and psychomotor skills&#46; Learning capacity&#44; short-term memory and spatial memory are affected at altitudes above 4500<span class="elsevierStyleHsp" style=""></span>m&#44; and more profoundly at more than 6000<span class="elsevierStyleHsp" style=""></span>m&#46; Symptom intensity varies according to ascent rate and altitude&#46;<a class="elsevierStyleCrossRefs" href="#bib0210"><span class="elsevierStyleSup">42&#44;43</span></a></p></span><span id="sec0095" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0145">Treatment</span><span id="sec0100" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0150">High-altitude headache</span><p id="par0150" class="elsevierStylePara elsevierViewall">Pharmacological treatment in the acute phase must distinguish isolated headache in AMS from cerebral oedema&#46; As HAH is frequently self-limited and remits in 2 or 3 days&#44; climbers are recommended to stop climbing&#44; rest&#44; and rehydrate when the condition presents&#46; If symptoms persist or worsen&#44; climbers should descend 500 to 1000<span class="elsevierStyleHsp" style=""></span>m&#46;<a class="elsevierStyleCrossRef" href="#bib0025"><span class="elsevierStyleSup">5</span></a> Adequate hydration&#44; analgesics and anti-inflammatory agents may improve symptoms&#46;<a class="elsevierStyleCrossRef" href="#bib0095"><span class="elsevierStyleSup">19</span></a></p><p id="par0155" class="elsevierStylePara elsevierViewall">HAH can be treated with paracetamol &#40;500-1000<span class="elsevierStyleHsp" style=""></span>mg&#41; and anti-inflammatory agents such as ibuprofen &#40;400-600<span class="elsevierStyleHsp" style=""></span>mg&#41;&#46;<a class="elsevierStyleCrossRefs" href="#bib0095"><span class="elsevierStyleSup">19&#44;44</span></a> Triptans are not effective&#44; although they can be useful for migraine associated with hypoxia&#46; At extreme altitudes&#44; supplementary oxygen &#40;2-4<span class="elsevierStyleHsp" style=""></span>L&#47;minute&#41; may be necessary during the night&#46;<a class="elsevierStyleCrossRef" href="#bib0035"><span class="elsevierStyleSup">7</span></a> Once oxygen therapy has been administered&#44; HAH should improve within about 15 minutes&#59; this event may be an indicator for ruling out migraine&#46;</p></span><span id="sec0105" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0155">Acute mountain sickness and cerebral oedema</span><p id="par0160" class="elsevierStylePara elsevierViewall">Pharmacological treatment of AMS is intended to increase ventilatory drive with drugs such as acetazolamide&#44; and reduce inflammation and cytokine release by means of steroids&#46;</p><p id="par0165" class="elsevierStylePara elsevierViewall">Acetazolamide is a carbonic anhydrase inhibitor that acts on the brain in addition to the blood cells&#44; renal tubules&#44; chemoreceptors&#44; and systemic and pulmonary vessels&#46; It provokes metabolic acidosis&#44; thus increasing respiratory minute volume&#46; Cerebral oedema can be treated with acetazolamide &#40;125-250<span class="elsevierStyleHsp" style=""></span>mg every 8-12<span class="elsevierStyleHsp" style=""></span>h&#41;&#44;<a class="elsevierStyleCrossRef" href="#bib0225"><span class="elsevierStyleSup">45</span></a> dexamethasone &#40;4<span class="elsevierStyleHsp" style=""></span>mg&#47;6<span class="elsevierStyleHsp" style=""></span>h&#44; orally&#41;&#44;<a class="elsevierStyleCrossRef" href="#bib0230"><span class="elsevierStyleSup">46</span></a> and&#47;or portable hyperbaric chamber &#40;193<span class="elsevierStyleHsp" style=""></span>mbar during 1<span class="elsevierStyleHsp" style=""></span>h&#41;&#44;<a class="elsevierStyleCrossRef" href="#bib0235"><span class="elsevierStyleSup">47</span></a> depending on intensity and severity of symptoms&#46;<a class="elsevierStyleCrossRef" href="#bib0240"><span class="elsevierStyleSup">48</span></a> Dexamethasone seems to block VEGF expression and reverts hypoxia-induced cerebral oedema&#46;<a class="elsevierStyleCrossRef" href="#bib0245"><span class="elsevierStyleSup">49</span></a></p></span></span><span id="sec0135" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0160">Prevention</span><span id="sec0140" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0165">High-altitude headache</span><p id="par0170" class="elsevierStylePara elsevierViewall">A slow ascent which promotes acclimation is recommended&#46; At 2500<span class="elsevierStyleHsp" style=""></span>m and above&#44; the maximum advisable ascent rate would be approximately 600<span class="elsevierStyleHsp" style=""></span>m per day&#46; This may reduce the incidence of AMS by 40&#37;&#46; Diet is also important and should be based on carbohydrates&#46; Alcohol should be avoided&#46;</p><p id="par0175" class="elsevierStylePara elsevierViewall">Results from the HEAT trial &#40;Headache Evaluation at Altitude Trial&#41; were published recently&#59; this clinical trial compared the effects of 600<span class="elsevierStyleHsp" style=""></span>mg ibuprofen or 85<span class="elsevierStyleHsp" style=""></span>mg acetazolamide or placebo for preventing HAH in 343 healthy subjects at 4300<span class="elsevierStyleHsp" style=""></span>m&#46;<a class="elsevierStyleCrossRef" href="#bib0250"><span class="elsevierStyleSup">50</span></a> Headache incidence rates were similar in participants treated with acetazolamide &#40;27&#46;1&#37;&#41; or ibuprofen &#40;27&#46;5&#37;&#41;&#44; and both were lower than that among participants receiving the placebo &#40;45&#46;3&#37;&#41;&#46; This suggests that both drugs in such doses are equally efficacious against HAH&#46;<a class="elsevierStyleCrossRef" href="#bib0250"><span class="elsevierStyleSup">50</span></a></p></span><span id="sec0120" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0170">Acute mountain sickness</span><p id="par0180" class="elsevierStylePara elsevierViewall">Individuals ascending above 3000<span class="elsevierStyleHsp" style=""></span>m or with a previous history of AMS-associated headache are recommended to take acetazolamide as preventive treatment&#46; The recommended preventive dosage is 125 to 250<span class="elsevierStyleHsp" style=""></span>mg every 12<span class="elsevierStyleHsp" style=""></span>hours&#44; at least 24<span class="elsevierStyleHsp" style=""></span>hours before ascent and for 2 days while the subject is at high altitude&#46;<a class="elsevierStyleCrossRefs" href="#bib0240"><span class="elsevierStyleSup">48&#44;51</span></a> Higher doses &#40;375<span class="elsevierStyleHsp" style=""></span>mg every 12<span class="elsevierStyleHsp" style=""></span>hours&#41; do not seem to be more efficacious than a dose of 125<span class="elsevierStyleHsp" style=""></span>mg every 12<span class="elsevierStyleHsp" style=""></span>hours&#46;<a class="elsevierStyleCrossRef" href="#bib0260"><span class="elsevierStyleSup">52</span></a> However&#44; results from the SPACE trial &#40;spironolactone and acetazolamide trial in the prevention of acute mountain sickness&#41; showed that spironolactone does not seem to prevent AMS compared to results from acetazolamide&#46;<a class="elsevierStyleCrossRef" href="#bib0265"><span class="elsevierStyleSup">53</span></a></p><p id="par0185" class="elsevierStylePara elsevierViewall">Dexamethasone &#40;8<span class="elsevierStyleHsp" style=""></span>mg per day&#44; administered in several doses&#41; is effective for preventing AMS because it reduces cytokine-release and capillary permeability&#46;<a class="elsevierStyleCrossRef" href="#bib0270"><span class="elsevierStyleSup">54</span></a> Prednisolone at a dose of 20<span class="elsevierStyleHsp" style=""></span>mg every 24<span class="elsevierStyleHsp" style=""></span>hours for 2 days before ascent and 3 days while at high altitude is also beneficial&#46;<a class="elsevierStyleCrossRef" href="#bib0275"><span class="elsevierStyleSup">55</span></a></p><p id="par0190" class="elsevierStylePara elsevierViewall">Ginkgo biloba extracts have been used to promote free radical elimination and prevent AMS&#46; However&#44; the PHAIT trial &#40;prevention of high altitude illness trial&#41; showed that it does not seem to be efficacious for preventing AMS compared to results from acetazolamide&#46;<a class="elsevierStyleCrossRef" href="#bib0280"><span class="elsevierStyleSup">56</span></a> Aspirin&#44; at a dose of 325<span class="elsevierStyleHsp" style=""></span>mg three times daily&#44; seems to reduce the incidence of headache associated with physical exertion at high altitude&#46;<a class="elsevierStyleCrossRef" href="#bib0285"><span class="elsevierStyleSup">57</span></a> Different recommendations on preventive measures for HAH&#44; are listed in <a class="elsevierStyleCrossRef" href="#tbl0025">Table 5</a> according to level of evidence&#46;</p><elsevierMultimedia ident="tbl0025"></elsevierMultimedia><p id="par0195" class="elsevierStylePara elsevierViewall">We need new clinical trials to confirm whether sumatriptan&#44; dosed at 50<span class="elsevierStyleHsp" style=""></span>mg before ascent&#44; is efficacious for preventing AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0290"><span class="elsevierStyleSup">58</span></a> Additional trials will have to confirm the results of a small study that found that low doses of theophylline &#40;300<span class="elsevierStyleHsp" style=""></span>mg per day for 5 days&#41; were efficacious for preventing AMS&#46;<a class="elsevierStyleCrossRef" href="#bib0295"><span class="elsevierStyleSup">59</span></a></p></span></span><span id="sec0125" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0175">Conclusion</span><p id="par0200" class="elsevierStylePara elsevierViewall">HAH can occur in isolation or as the main symptom of AMS&#46; In any case&#44; clinical symptoms seem to display a progressive pattern along the continuum of HAH&#44; AMS&#44; and HACE&#46; At present&#44; the recent discoveries of different chemical mediators provide us with a better understanding of the pathogenesis of this continuum and of the therapeutic targets acted upon by acetazolamide and steroids&#46;</p></span><span id="sec0130" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0180">Conflicts of interest</span><p id="par0205" class="elsevierStylePara elsevierViewall">The author has no conflicts of interest to declare&#46;</p></span></span>"
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    "fechaRecibido" => "2012-03-12"
    "fechaAceptado" => "2012-04-21"
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            0 => "Altitude"
            1 => "Acetazolamide"
            2 => "Headache"
            3 => "Lake Louise Questionnaire"
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            0 => "Altitud"
            1 => "Acetazolamida"
            2 => "Cefalea"
            3 => "Cuestionario Lago Louise"
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        "resumen" => "<span class="elsevierStyleSectionTitle" id="sect0010">Introduction</span><p id="spar0020" class="elsevierStyleSimplePara elsevierViewall">Headache is the most common complication associated with exposure to high altitude&#44; and can appear as an isolated high-altitude headache &#40;HAH&#41; or in conjunction with acute mountain sickness &#40;AMS&#41;&#46; The purpose of this article is to review several aspects related to diagnosis and treatment of HAH&#46;</p> <span class="elsevierStyleSectionTitle" id="sect0015">Development</span><p id="spar0025" class="elsevierStyleSimplePara elsevierViewall">HAH occurs in 80&#37; of all individuals at altitudes higher than 3000<span class="elsevierStyleHsp" style=""></span>m&#46; The second edition of ICHD-II includes HAH in the chapter entitled &#8220;Headaches attributed to disorder of homeostasis&#8221;&#46; Hypoxia elicits a neurohumoral and haemodynamic response that may provoke increased capillary pressure and oedema&#46; Hypoxia-induced cerebral vasodilation is a probable cause of HAH&#46; The main symptom of AMS is headache&#44; frequently accompanied by sleep disorders&#44; fatigue&#44; dizziness and instability&#44; nausea and anorexia&#46; Some degree of individual susceptibility and considerable inter-individual variability seem to be present in AMS&#46; High-altitude cerebral oedema is the most severe form of AMS&#44; and may occur above 2500<span class="elsevierStyleHsp" style=""></span>m&#46; Brain MRI studies have found variable degrees of oedema in subcortical white matter and the splenium of the corpus callosum&#46; HAH can be treated with paracetamol or ibuprofen&#46; Pharmacological treatment of AMS is intended to increase ventilatory drive with drugs such as acetazolamide&#44; and reduce inflammation and cytokine release by means of steroids&#46;</p> <span class="elsevierStyleSectionTitle" id="sect0020">Conclusions</span><p id="spar0030" class="elsevierStyleSimplePara elsevierViewall">Symptom escalation seems to be present along the continuum containing HAH&#44; AMS&#44; and high-altitude cerebral oedema&#46;</p>"
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      "es" => array:2 [
        "titulo" => "Resumen"
        "resumen" => "<span class="elsevierStyleSectionTitle" id="sect0030">Introducci&#243;n</span><p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">La cefalea es la complicaci&#243;n m&#225;s frecuente de la exposici&#243;n a la altitud y puede aparecer de forma aislada o bien asociada al mal de altura &#40;MA&#41;&#46; El objetivo de este art&#237;culo es revisar los aspectos relacionados con el diagn&#243;stico y tratamiento de la cefalea de elevada altitud &#40;CEA&#41;&#46;</p> <span class="elsevierStyleSectionTitle" id="sect0035">Desarrollo</span><p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">El 80&#37; de las personas presentan CEA por encima de los 3&#46;000<span class="elsevierStyleHsp" style=""></span>m de altitud&#46; La segunda versi&#243;n de la <span class="elsevierStyleItalic">Internacional Classification of Headache Disorders</span> &#40;ICHD-II&#41; incluye la CEA en el cap&#237;tulo &#171;Cefalea atribuida a trastornos de la homeostasia&#187;&#46; La hipoxia desencadena una respuesta neurohumoral y hemodin&#225;mica que provoca un aumento de la presi&#243;n capilar y edema&#46; La vasodilataci&#243;n cerebral inducida por hipoxia es una causa probable de CEA&#46; El s&#237;ntoma cardinal del MA es la cefalea&#44; que se suele asociar con trastornos del sue&#241;o&#44; fatiga&#44; mareo e inestabilidad&#44; n&#225;useas y anorexia&#46; Parece existir una cierta susceptibilidad as&#237; como una gran variaci&#243;n interindividual&#46; La forma m&#225;s grave es el edema cerebral de altitud y puede suceder por encima de los 2&#46;500<span class="elsevierStyleHsp" style=""></span>m&#46; Estudios de resonancia de enc&#233;falo han mostrado la presencia de edema en sustancia blanca y esplenio del cuerpo calloso&#46; La CEA puede tratarse con paracetamol e ibuprofeno&#46; El tratamiento farmacol&#243;gico del MA tiene la finalidad de incrementar la respuesta ventilatoria&#44; mediante f&#225;rmacos como la acetazolamida&#44; y reducir los procesos inflamatorios y de liberaci&#243;n de citocinas&#44; mediante el empleo de esteroides&#46;</p> <span class="elsevierStyleSectionTitle" id="sect0040">Conclusiones</span><p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">Parece haber una progresi&#243;n en la expresi&#243;n de los s&#237;ntomas entre la CEA&#44; el MA y el edema cerebral de altitud&#46;</p>"
      ]
    ]
    "NotaPie" => array:2 [
      0 => array:2 [
        "etiqueta" => "&#9734;"
        "nota" => "<p class="elsevierStyleNotepara" id="npar0005">Please cite this article as&#58; Carod-Artal FJ&#46; Cefalea de elevada altitud y mal de altura&#46; Neurolog&#237;a&#46; 2014&#59;29&#58;533&#8211;540&#46;</p>"
      ]
      1 => array:2 [
        "etiqueta" => "&#9734;&#9734;"
        "nota" => "<p class="elsevierStyleNotepara" id="npar0010">This study was presented as a lecture to the Headache Study Group at the 63rd Annual Meeting of the Spanish Society of Neurology&#44; November 2011&#44; Barcelona&#46;</p>"
      ]
    ]
    "multimedia" => array:5 [
      0 => array:7 [
        "identificador" => "tbl0005"
        "etiqueta" => "Table 1"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">A&#46; Headache must present with at least 2 of the following characteristics and fulfil criteria C and D&#58;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>1&#46; Bilateral&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>2&#46; Frontal or frontotemporal&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>3&#46; Dull or pressing pain&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>4&#46; Mild to moderate intensity&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>5&#46; Aggravated by exertion&#44; movement&#44; straining&#44; coughing&#44; or bending down&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">B&#46; Ascent to altitudes above 2500<span class="elsevierStyleHsp" style=""></span>m&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">C&#46; Headache develops within 24<span class="elsevierStyleHsp" style=""></span>hours after ascent&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">D&#46; Headache resolves within 8<span class="elsevierStyleHsp" style=""></span>hours after descent&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab584436.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0035" class="elsevierStyleSimplePara elsevierViewall">Diagnostic criteria for HAH</p>"
        ]
      ]
      1 => array:7 [
        "identificador" => "tbl0010"
        "etiqueta" => "Table 2"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "tabla" => array:2 [
          "leyenda" => "<p id="spar0045" class="elsevierStyleSimplePara elsevierViewall">masl&#58; metres above sea level&#46;</p>"
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Altitude reached&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Sleeping at high altitude&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Individual susceptibility&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Rate and mode of ascent&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Prior history of AMS&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Residence below 900<span class="elsevierStyleHsp" style=""></span>masl&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Intense exertion&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Dehydration&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Obesity&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Age &#40;young people&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">History of cardiopulmonary disease&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab584435.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0040" class="elsevierStyleSimplePara elsevierViewall">Risk factors for HAH</p>"
        ]
      ]
      2 => array:7 [
        "identificador" => "tbl0015"
        "etiqueta" => "Table 3"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Cerebral oedema&#47;severe AMS&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Hypoxia-&#47;hypobaria-induced migraine&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Headache secondary to viral process&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Effects associated with alcohol&#44; addictive drugs&#44; and toxic chemicals&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Carbon monoxide poisoning&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Brain tumour&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Arteriovenous malformations&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">CNS infection&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Dehydration&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Metabolic disorders&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>Diabetic ketoacidosis&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>Hypothermia&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>Hyponatraemia&#47;hypoglycaemia&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab584434.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0050" class="elsevierStyleSimplePara elsevierViewall">Differential diagnosis for HAH</p>"
        ]
      ]
      3 => array:7 [
        "identificador" => "tbl0020"
        "etiqueta" => "Table 4"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "tabla" => array:2 [
          "leyenda" => "<p id="spar0060" class="elsevierStyleSimplePara elsevierViewall">masl&#58; metres above sea level&#46;</p>"
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><tbody title="tbody"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Headache in non-acclimated individuals who ascend rapidly to an altitude above 2500<span class="elsevierStyleHsp" style=""></span>m&#44; and at least 1 of the following symptoms&#58;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>- Gastrointestinal&#58; anorexia&#44; nausea and vomiting&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>- Insomnia&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>- Dizziness&#47;vertigo&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>- Fatigue&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleHsp" style=""></span>- Onset within 6-24<span class="elsevierStyleHsp" style=""></span>hours after ascent&#44; sometimes within the first hour&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab584432.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0055" class="elsevierStyleSimplePara elsevierViewall">Lake Louise diagnostic criteria for AMS</p>"
        ]
      ]
      4 => array:7 [
        "identificador" => "tbl0025"
        "etiqueta" => "Table 5"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "tabla" => array:2 [
          "leyenda" => "<p id="spar0070" class="elsevierStyleSimplePara elsevierViewall">masl&#58; metres above sea level&#46;</p>"
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" style="border-bottom: 2px solid black">Procedure&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" style="border-bottom: 2px solid black">Dose&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" style="border-bottom: 2px solid black">Evidence&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" style="border-bottom: 2px solid black">Recommendations&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Slow ascent&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#60;300<span class="elsevierStyleHsp" style=""></span>masl&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">A&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Acetazolamide&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">250<span class="elsevierStyleHsp" style=""></span>mg to 1<span class="elsevierStyleHsp" style=""></span>g&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">A&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Dexamethasone&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8<span class="elsevierStyleHsp" style=""></span>mg&#47;d&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">A&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Supplementary O<span class="elsevierStyleInf">2</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2<span class="elsevierStyleHsp" style=""></span>L&#47;min&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
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                  \t\t\t\t">2&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">A&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Theophylline&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">375<span class="elsevierStyleHsp" style=""></span>mg&#47;12<span class="elsevierStyleHsp" style=""></span>h&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">B&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Sumatriptan&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">50<span class="elsevierStyleHsp" style=""></span>mg&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">B&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Carbohydrate-rich diet&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">3&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">C&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">Ginkgo biloba</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">240<span class="elsevierStyleHsp" style=""></span>mg&#47;d&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">3&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">C&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
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          "en" => "<p id="spar0065" class="elsevierStyleSimplePara elsevierViewall">Recommended preventive measures for HAH according to the level of evidence</p>"
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                      "titulo" => "The great breathlessness mountains"
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                        0 => array:2 [
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                          "autores" => array:1 [
                            0 => "D&#46; Rennie"
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                    0 => array:1 [
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                        "tituloSerie" => "J Am Med Assoc"
                        "fecha" => "1986"
                        "volumen" => "256"
                        "paginaInicial" => "81"
                        "paginaFinal" => "82"
                      ]
                    ]
                  ]
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                      "titulo" => "La pression barometrique"
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                            0 => "P&#46; Bert"
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                        "fecha" => "1878"
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                      ]
                    ]
                  ]
                ]
              ]
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              "identificador" => "bib0015"
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                0 => array:2 [
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                      "titulo" => "Some experiences of mountain sickness in the Andes"
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                            0 => "T&#46;H&#46; Ravenhill"
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                      "Revista" => array:5 [
                        "tituloSerie" => "J Trop Med Hyg"
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                        "volumen" => "16"
                        "paginaInicial" => "313"
                        "paginaFinal" => "320"
                      ]
                    ]
                  ]
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                            0 => "M&#46;H&#46; Wilson"
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                      "doi" => "10.1016/S1474-4422(09)70014-6"
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                        "tituloSerie" => "Lancet Neurol"
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                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/19161909"
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                    0 => array:2 [
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                      "titulo" => "Acute mountain sickness&#58; pathophysiology&#44; prevention&#44; and treatment"
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                          "etal" => false
                          "autores" => array:4 [
                            0 => "C&#46; Imray"
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                      "doi" => "10.1016/j.pcad.2010.02.003"
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                            2 => "D&#46;J&#46; Collier"
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                      "titulo" => "Efficacy of oxygen inhalation in sumatriptan refractory &#8220;high altitude&#8221; cluster headache attacks"
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                    0 => array:2 [
                      "doi" => "10.1007/s10194-009-0160-0"
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                        0 => array:2 [
                          "etal" => true
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                            4 => "M&#46; Maggiorini"
                            5 => "M&#46; Schneider"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2005.6.158"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2005"
                        "volumen" => "6"
                        "paginaInicial" => "158"
                        "paginaFinal" => "166"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16060850"
                            "web" => "Medline"
                          ]
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                      ]
                    ]
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                ]
              ]
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                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Identifying the possible risk factors for high-altitude headache in mountaineers"
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                        0 => array:2 [
                          "etal" => false
                          "autores" => array:1 [
                            0 => "J&#46;S&#46; Lawley"
                          ]
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                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1177/0333102411422385"
                      "Revista" => array:6 [
                        "tituloSerie" => "Cephalalgia"
                        "fecha" => "2011"
                        "volumen" => "31"
                        "paginaInicial" => "1677"
                        "paginaFinal" => "1678"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21926157"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            13 => array:3 [
              "identificador" => "bib0070"
              "etiqueta" => "14"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Risk factors for high-altitude headache in mountaineers"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:4 [
                            0 => "M&#46; Burtscher"
                            1 => "K&#46; Mairer"
                            2 => "M&#46; Wille"
                            3 => "G&#46; Broessner"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1177/0333102410394678"
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                        "tituloSerie" => "Cephalalgia"
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                        "volumen" => "31"
                        "paginaInicial" => "706"
                        "paginaFinal" => "711"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21220379"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            14 => array:3 [
              "identificador" => "bib0075"
              "etiqueta" => "15"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Effects of high altitude exposure on cerebral hemodynamics in normal subjects"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "A&#46; Van Osta"
                            1 => "J&#46;J&#46; Moraine"
                            2 => "C&#46; M&#233;lot"
                            3 => "H&#46; Mairb&#228;url"
                            4 => "M&#46; Maggiorini"
                            5 => "R&#46; Naeije"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1161/01.STR.0000155735.85888.13"
                      "Revista" => array:6 [
                        "tituloSerie" => "Stroke"
                        "fecha" => "2005"
                        "volumen" => "36"
                        "paginaInicial" => "557"
                        "paginaFinal" => "560"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15692117"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            15 => array:3 [
              "identificador" => "bib0080"
              "etiqueta" => "16"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Cerebral artery dilatation maintains cerebral oxygenation at extreme altitude and in acute hypoxia &#8211; an ultrasound and MRI study"
                      "autores" => array:1 [
                        0 => array:3 [
                          "colaboracion" => "Caudwell Xtreme Everest Research Group"
                          "etal" => true
                          "autores" => array:6 [
                            0 => "M&#46;H&#46; Wilson"
                            1 => "M&#46;E&#46; Edsell"
                            2 => "I&#46; Davagnanam"
                            3 => "S&#46;P&#46; Hirani"
                            4 => "D&#46;S&#46; Martin"
                            5 => "D&#46;Z&#46; Levett"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1038/jcbfm.2011.81"
                      "Revista" => array:6 [
                        "tituloSerie" => "J Cereb Blood Flow Metab"
                        "fecha" => "2011"
                        "volumen" => "31"
                        "paginaInicial" => "2019"
                        "paginaFinal" => "2029"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21654697"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            16 => array:3 [
              "identificador" => "bib0085"
              "etiqueta" => "17"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Sea-level assessment of dynamic cerebral autoregulation predicts susceptibility to acute mountain sickness at high altitude"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "N&#46;J&#46; Cochand"
                            1 => "M&#46; Wild"
                            2 => "J&#46;V&#46; Brugniaux"
                            3 => "P&#46;J&#46; Davies"
                            4 => "K&#46;A&#46; Evans"
                            5 => "R&#46;G&#46; Wise"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1161/STROKEAHA.111.621714"
                      "Revista" => array:6 [
                        "tituloSerie" => "Stroke"
                        "fecha" => "2011"
                        "volumen" => "42"
                        "paginaInicial" => "3628"
                        "paginaFinal" => "3630"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21960569"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            17 => array:3 [
              "identificador" => "bib0090"
              "etiqueta" => "18"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High altitude headache&#46; Lessons from headaches at sea level"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:2 [
                            0 => "M&#46; Sanchez del Rio"
                            1 => "M&#46;A&#46; Moskowitz"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Adv Exp Med Biol"
                        "fecha" => "1999"
                        "volumen" => "474"
                        "paginaInicial" => "145"
                        "paginaFinal" => "153"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/10634999"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            18 => array:3 [
              "identificador" => "bib0095"
              "etiqueta" => "19"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High-altitude headache"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:2 [
                            0 => "L&#46;P&#46; Queiroz"
                            1 => "A&#46;M&#46; Rapoport"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Curr Pain Headache Rep"
                        "fecha" => "2007"
                        "volumen" => "11"
                        "paginaInicial" => "293"
                        "paginaFinal" => "296"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17686393"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            19 => array:3 [
              "identificador" => "bib0100"
              "etiqueta" => "20"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Acute mountain sickness and ascent rates in trekkers above 2500<span class="elsevierStyleHsp" style=""></span>m in the Nepali Himalaya"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:2 [
                            0 => "J&#46; Vardy"
                            1 => "K&#46; Judge"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Aviat Space Environ Med"
                        "fecha" => "2006"
                        "volumen" => "77"
                        "paginaInicial" => "742"
                        "paginaFinal" => "744"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16856361"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            20 => array:3 [
              "identificador" => "bib0105"
              "etiqueta" => "21"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Medicine at high altitude"
                      "autores" => array:1 [
                        0 => array:3 [
                          "colaboracion" => "Birmingham Medical Research Expeditionary Society"
                          "etal" => false
                          "autores" => array:1 [
                            0 => "A&#46;D&#46; Wright"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Clin Med"
                        "fecha" => "2006"
                        "volumen" => "6"
                        "paginaInicial" => "604"
                        "paginaFinal" => "608"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17228562"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            21 => array:3 [
              "identificador" => "bib0110"
              "etiqueta" => "22"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High altitude arrhythmias"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "D&#46;R&#46; Woods"
                            1 => "S&#46; Allen"
                            2 => "T&#46;R&#46; Betts"
                            3 => "D&#46; Gardiner"
                            4 => "H&#46; Montgomery"
                            5 => "J&#46;M&#46; Morgan"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1159/000127445"
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                        "tituloSerie" => "Cardiology"
                        "fecha" => "2008"
                        "volumen" => "111"
                        "paginaInicial" => "239"
                        "paginaFinal" => "246"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18434732"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            22 => array:3 [
              "identificador" => "bib0115"
              "etiqueta" => "23"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Genetic variation in hypoxia inducible factor 1alpha and its possible association with high altitude adaptation in Sherpas"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "K&#46; Suzuki"
                            1 => "T&#46; Kizaki"
                            2 => "Y&#46; Hitomi"
                            3 => "M&#46; Nukita"
                            4 => "K&#46; Kimoto"
                            5 => "N&#46; Miyazawa"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Med Hypotheses"
                        "fecha" => "2003"
                        "volumen" => "61"
                        "paginaInicial" => "385"
                        "paginaFinal" => "389"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12944107"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            23 => array:3 [
              "identificador" => "bib0120"
              "etiqueta" => "24"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Acute mountain sickness&#58; medical problems associated with acute and subacute exposure to hypobaric hypoxia"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:1 [
                            0 => "C&#46; Clarke"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1136/pgmj.2006.047662"
                      "Revista" => array:6 [
                        "tituloSerie" => "Postgrad Med J"
                        "fecha" => "2006"
                        "volumen" => "82"
                        "paginaInicial" => "748"
                        "paginaFinal" => "753"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17099095"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            24 => array:3 [
              "identificador" => "bib0125"
              "etiqueta" => "25"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Hypoxia-inducible factor-1 mediates activation of cultured vascular endothelial cells by inducing multiple angiogenic factors"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "M&#46; Yamakawa"
                            1 => "L&#46;X&#46; Liu"
                            2 => "T&#46; Date"
                            3 => "A&#46;J&#46; Belanger"
                            4 => "K&#46;A&#46; Vincent"
                            5 => "G&#46;Y&#46; Akita"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1161/01.RES.0000093984.48643.D7"
                      "Revista" => array:6 [
                        "tituloSerie" => "Circ Res"
                        "fecha" => "2003"
                        "volumen" => "93"
                        "paginaInicial" => "664"
                        "paginaFinal" => "673"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12958144"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            25 => array:3 [
              "identificador" => "bib0130"
              "etiqueta" => "26"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Hypothesis&#58; angiogenesis cytokines in high altitude cerebral oedema"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:1 [
                            0 => "J&#46;W&#46; Severinghaus"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Acta Anaesthesiol Scand Suppl"
                        "fecha" => "1995"
                        "volumen" => "107"
                        "paginaInicial" => "177"
                        "paginaFinal" => "178"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/8599273"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            26 => array:3 [
              "identificador" => "bib0135"
              "etiqueta" => "27"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The Lake Louise Acute Mountain Sickness scoring system"
                      "autores" => array:1 [
                        0 => array:3 [
                          "colaboracion" => "The Lake Louise AMS Scoring Consensus Committee"
                          "etal" => false
                          "autores" => array:4 [
                            0 => "R&#46;C&#46; Roach"
                            1 => "P&#46; Bartsch"
                            2 => "P&#46;H&#46; Hackett"
                            3 => "O&#46; Oelz"
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                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:4 [
                        "titulo" => "Hypoxia and molecular medicine"
                        "paginaInicial" => "273"
                        "paginaFinal" => "274"
                        "serieFecha" => "1993"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            27 => array:3 [
              "identificador" => "bib0140"
              "etiqueta" => "28"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Comparing questionnaires for the assessment of acute mountain sickness"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:4 [
                            0 => "P&#46; Dellasanta"
                            1 => "S&#46; Gaillard"
                            2 => "L&#46; Loutan"
                            3 => "B&#46; Kayser"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2007.8305"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2007"
                        "volumen" => "8"
                        "paginaInicial" => "184"
                        "paginaFinal" => "191"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17824818"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
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            28 => array:3 [
              "identificador" => "bib0145"
              "etiqueta" => "29"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Propiedades m&#233;tricas de la versi&#243;n espa&#241;ola del Cuestionario de Mal de Altura del Lago Louise"
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                        0 => array:2 [
                          "etal" => false
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                            0 => "F&#46;J&#46; Carod-Artal"
                            1 => "D&#46; Ezpeleta Ech&#225;varri"
                            2 => "A&#46;L&#46; Guerrero Peral"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1016/j.nrl.2010.12.014"
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                        "tituloSerie" => "Neurolog&#237;a"
                        "fecha" => "2011"
                        "volumen" => "26"
                        "paginaInicial" => "337"
                        "paginaFinal" => "342"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21354668"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            29 => array:3 [
              "identificador" => "bib0150"
              "etiqueta" => "30"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The environmental symptoms questionnaire&#58; revisions and new field data"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:2 [
                            0 => "J&#46;B&#46; Sampson"
                            1 => "J&#46;L&#46; Kobrick"
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                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Aviat Space Environ Med"
                        "fecha" => "1980"
                        "volumen" => "51"
                        "paginaInicial" => "872"
                        "paginaFinal" => "877"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/7417157"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            30 => array:3 [
              "identificador" => "bib0155"
              "etiqueta" => "31"
              "referencia" => array:1 [
                0 => array:2 [
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                    0 => array:2 [
                      "titulo" => "Who should not go high&#58; chronic disease and work at altitude during construction of the Qinghai-Tibet railroad"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "T&#46;Y&#46; Wu"
                            1 => "S&#46;Q&#46; Ding"
                            2 => "J&#46;L&#46; Liu"
                            3 => "M&#46;T&#46; Yu"
                            4 => "J&#46;H&#46; Jia"
                            5 => "Z&#46;C&#46; Chai"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2007.1015"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2007"
                        "volumen" => "8"
                        "paginaInicial" => "88"
                        "paginaFinal" => "107"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17584003"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            31 => array:3 [
              "identificador" => "bib0160"
              "etiqueta" => "32"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Incidence of high altitude illnesses among unacclimatized persons who acutely ascended to Tibet"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "Y&#46; Ren"
                            1 => "Z&#46; Fu"
                            2 => "W&#46; Shen"
                            3 => "P&#46; Jiang"
                            4 => "Y&#46; He"
                            5 => "S&#46; Peng"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2009.1049"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2010"
                        "volumen" => "11"
                        "paginaInicial" => "39"
                        "paginaFinal" => "42"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/20367487"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            32 => array:3 [
              "identificador" => "bib0165"
              "etiqueta" => "33"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Altitude illness&#58; risk factors&#44; prevention&#44; presentation&#44; and treatment"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "D&#46;C&#46; Fiore"
                            1 => "S&#46; Hall"
                            2 => "P&#46; Shoja"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Am Fam Physician"
                        "fecha" => "2010"
                        "volumen" => "82"
                        "paginaInicial" => "1103"
                        "paginaFinal" => "1110"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21121556"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            33 => array:3 [
              "identificador" => "bib0170"
              "etiqueta" => "34"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High altitude cerebral edema"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:2 [
                            0 => "P&#46;H&#46; Hackett"
                            1 => "R&#46;C&#46; Roach"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/1527029041352054"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2004"
                        "volumen" => "5"
                        "paginaInicial" => "136"
                        "paginaFinal" => "146"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15265335"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            34 => array:3 [
              "identificador" => "bib0175"
              "etiqueta" => "35"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Magnetic resonance imaging evidence of cytotoxic cerebral edema in acute sickness"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "K&#46; Kallenberg"
                            1 => "D&#46;M&#46; Bailey"
                            2 => "S&#46; Christ"
                            3 => "A&#46; Mohr"
                            4 => "R&#46; Roukens"
                            5 => "E&#46; Menold"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1038/sj.jcbfm.9600404"
                      "Revista" => array:6 [
                        "tituloSerie" => "J Cereb Blood Flow Metab"
                        "fecha" => "2007"
                        "volumen" => "27"
                        "paginaInicial" => "1064"
                        "paginaFinal" => "1071"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/17024110"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            35 => array:3 [
              "identificador" => "bib0180"
              "etiqueta" => "36"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High-altitude cerebral edema evaluated with magnetic resonance imaging&#58; clinical correlation and pathophysiology"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "P&#46;H&#46; Hackett"
                            1 => "P&#46;R&#46; Yarnell"
                            2 => "R&#46; Hill"
                            3 => "K&#46; Reynard"
                            4 => "J&#46; Heit"
                            5 => "J&#46; McCormick"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J Am Med Assoc"
                        "fecha" => "1998"
                        "volumen" => "280"
                        "paginaInicial" => "1920"
                        "paginaFinal" => "1925"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            36 => array:3 [
              "identificador" => "bib0185"
              "etiqueta" => "37"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Microhemorrhages in nonfatal high-altitude cerebral edema"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "K&#46; Kallenberg"
                            1 => "C&#46; Dehnert"
                            2 => "A&#46; Dorfler"
                            3 => "P&#46;D&#46; Schellinger"
                            4 => "D&#46;M&#46; Bailey"
                            5 => "M&#46; Knauth"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1038/jcbfm.2008.55"
                      "Revista" => array:6 [
                        "tituloSerie" => "J Cereb Blood Flow Metab"
                        "fecha" => "2008"
                        "volumen" => "28"
                        "paginaInicial" => "1635"
                        "paginaFinal" => "1642"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18523438"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            37 => array:3 [
              "identificador" => "bib0190"
              "etiqueta" => "38"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The headache of high altitude and microgravity &#8211; similarities with clinical syndromes of cerebral venous hypertension"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "M&#46;H&#46; Wilson"
                            1 => "C&#46;H&#46; Imray"
                            2 => "A&#46;R&#46; Hargens"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2011.1026"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2011"
                        "volumen" => "12"
                        "paginaInicial" => "379"
                        "paginaFinal" => "386"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/22087727"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            38 => array:3 [
              "identificador" => "bib0195"
              "etiqueta" => "39"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Neurological conditions at altitude that fall outside the usual definition of altitude sickness"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "B&#46; Basnyat"
                            1 => "T&#46; Wu"
                            2 => "J&#46;H&#46; Gertsch"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/1527029041352126"
                      "Revista" => array:6 [
                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2004"
                        "volumen" => "5"
                        "paginaInicial" => "171"
                        "paginaFinal" => "179"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/15265338"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            39 => array:3 [
              "identificador" => "bib0200"
              "etiqueta" => "40"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Cerebral thrombosis at altitude&#58; its pathogenesis and the problems of prevention and treatment"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "S&#46;Y&#46; Song"
                            1 => "T&#46; Asaji"
                            2 => "Y&#46; Tanizaki"
                            3 => "T&#46; Fujimaki"
                            4 => "M&#46; Matsutani"
                            5 => "R&#46; Okeda"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Aviat Space Environ Med"
                        "fecha" => "1986"
                        "volumen" => "57"
                        "paginaInicial" => "71"
                        "paginaFinal" => "76"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/3942573"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            40 => array:3 [
              "identificador" => "bib0205"
              "etiqueta" => "41"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Altitude-related deaths in seven trekkers in the Himalayas"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:4 [
                            0 => "J&#46; Dickinson"
                            1 => "D&#46; Health"
                            2 => "J&#46; Gosney"
                            3 => "D&#46; Williams"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Thorax"
                        "fecha" => "1983"
                        "volumen" => "38"
                        "paginaInicial" => "646"
                        "paginaFinal" => "656"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/6623417"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            41 => array:3 [
              "identificador" => "bib0210"
              "etiqueta" => "42"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Verbal free recall in high altitude&#58; proper names vs common names"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "G&#46; Pelamatti"
                            1 => "M&#46; Pascotto"
                            2 => "C&#46; Semenza"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Cortex"
                        "fecha" => "2003"
                        "volumen" => "39"
                        "paginaInicial" => "97"
                        "paginaFinal" => "103"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12627756"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            42 => array:3 [
              "identificador" => "bib0215"
              "etiqueta" => "43"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Cognition and metacognition at extreme altitudes on Mount Everest"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "T&#46;O&#46; Nelson"
                            1 => "J&#46; Dunlosky"
                            2 => "D&#46;M&#46; White"
                            3 => "J&#46; Steinberg"
                            4 => "B&#46;D&#46; Townes"
                            5 => "D&#46; Anderson"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "J Exp Psychol Gen"
                        "fecha" => "1990"
                        "volumen" => "119"
                        "paginaInicial" => "367"
                        "paginaFinal" => "374"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/2148573"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            43 => array:3 [
              "identificador" => "bib0220"
              "etiqueta" => "44"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High altitude headache&#58; efficacy of acetaminophen vs&#46; ibuprofen in a randomized&#44; controlled trial"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "N&#46;S&#46; Harris"
                            1 => "R&#46;P&#46; Wenzel"
                            2 => "S&#46;H&#46; Thomas"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "J Emerg Med"
                        "fecha" => "2003"
                        "volumen" => "24"
                        "paginaInicial" => "383"
                        "paginaFinal" => "387"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12745039"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            44 => array:3 [
              "identificador" => "bib0225"
              "etiqueta" => "45"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Acetazolamide in the treatment of acute mountain sickness&#58; clinical efficacy and effect on gas exchange"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:4 [
                            0 => "C&#46;K&#46; Grissom"
                            1 => "R&#46;C&#46; Roach"
                            2 => "F&#46;H&#46; Sarnquist"
                            3 => "P&#46;H&#46; Hackett"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Ann Intern Med"
                        "fecha" => "1992"
                        "volumen" => "116"
                        "paginaInicial" => "461"
                        "paginaFinal" => "465"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/1739236"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            45 => array:3 [
              "identificador" => "bib0230"
              "etiqueta" => "46"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Dexamethasone for prevention and treatment of acute mountain sickness"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => true
                          "autores" => array:6 [
                            0 => "P&#46;H&#46; Hackett"
                            1 => "R&#46;C&#46; Roach"
                            2 => "R&#46;A&#46; Wood"
                            3 => "R&#46;G&#46; Foutch"
                            4 => "R&#46;T&#46; Meehan"
                            5 => "D&#46; Rennie"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Aviat Space Environ Med"
                        "fecha" => "1988"
                        "volumen" => "59"
                        "paginaInicial" => "950"
                        "paginaFinal" => "954"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/3190622"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            46 => array:3 [
              "identificador" => "bib0235"
              "etiqueta" => "47"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Treatment of acute mountain sickness by simulated descent&#58; a randomised controlled trial"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "P&#46; B&#228;rtsch"
                            1 => "B&#46; Merki"
                            2 => "D&#46; Hofstetter"
                            3 => "M&#46; Maggiorini"
                            4 => "B&#46; Kayser"
                            5 => "O&#46; Oelz"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Br Med J"
                        "fecha" => "1993"
                        "volumen" => "306"
                        "paginaInicial" => "1098"
                        "paginaFinal" => "1101"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            47 => array:3 [
              "identificador" => "bib0240"
              "etiqueta" => "48"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "High hopes at high altitudes&#58; pharmacotherapy for acute mountain sickness and high-altitude cerebral and pulmonary oedema"
                      "autores" => array:1 [
                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "A&#46; Wright"
                            1 => "S&#46; Brearey"
                            2 => "C&#46; Imray"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1517/14656566.9.1.119"
                      "Revista" => array:7 [
                        "tituloSerie" => "Expert Opin Pharmacother"
                        "fecha" => "2008"
                        "volumen" => "9"
                        "paginaInicial" => "119"
                        "paginaFinal" => "127"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/18076343"
                            "web" => "Medline"
                          ]
                        ]
                        "itemHostRev" => array:3 [
                          "pii" => "S1873994611002510"
                          "estado" => "S300"
                          "issn" => "18739946"
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            48 => array:3 [
              "identificador" => "bib0245"
              "etiqueta" => "49"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Hypoxia-induced vascular endothelial growth factor expression causes vascular leakage in the brain"
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                        0 => array:2 [
                          "etal" => false
                          "autores" => array:3 [
                            0 => "H&#46;J&#46; Schoch"
                            1 => "S&#46; Fischer"
                            2 => "H&#46;H&#46; Marti"
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                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:6 [
                        "tituloSerie" => "Brain"
                        "fecha" => "2002"
                        "volumen" => "125"
                        "paginaInicial" => "2549"
                        "paginaFinal" => "2557"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/12390979"
                            "web" => "Medline"
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                ]
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              "identificador" => "bib0250"
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                        ]
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                    ]
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                      "titulo" => "Efficacy and harm of pharmacological prevention of acute mountain sickness&#58; quantitative systematic review"
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                          "autores" => array:3 [
                            0 => "L&#46; Dumont"
                            1 => "C&#46; Mardirosoff"
                            2 => "M&#46;R&#46; Tram&#232;r"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Br Med J"
                        "fecha" => "2000"
                        "volumen" => "321"
                        "paginaInicial" => "267"
                        "paginaFinal" => "277"
                      ]
                    ]
                  ]
                ]
              ]
            ]
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              "identificador" => "bib0260"
              "etiqueta" => "52"
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                0 => array:2 [
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                    0 => array:2 [
                      "titulo" => "Acetazolamide 125<span class="elsevierStyleHsp" style=""></span>mg BD is not significantly different from 375<span class="elsevierStyleHsp" style=""></span>mg BD in the prevention of acute mountain sickness&#58; the prophylactic acetazolamide dosage comparison for efficacy &#40;PACE&#41; trial"
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                          "etal" => true
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                            2 => "P&#46;S&#46; Holck"
                            3 => "E&#46;W&#46; Johnson"
                            4 => "A&#46;M&#46; Luks"
                            5 => "B&#46;P&#46; Donham"
                          ]
                        ]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1089/ham.2006.7.17"
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                        "tituloSerie" => "High Alt Med Biol"
                        "fecha" => "2006"
                        "volumen" => "7"
                        "paginaInicial" => "17"
                        "paginaFinal" => "27"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/16544963"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
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              "identificador" => "bib0265"
              "etiqueta" => "53"
              "referencia" => array:1 [
                0 => array:2 [
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                    0 => array:2 [
                      "titulo" => "Spironolactone does not prevent acute mountain sickness&#58; a prospective&#44; double-blind&#44; randomized&#44; placebo-controlled trial by SPACE Trial Group &#40;spironolactone and acetazolamide trial in the prevention of acute mountain sickness group&#41;"
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                            2 => "M&#46; Pun"
                            3 => "S&#46; Halverson"
                            4 => "P&#46; Szawarski"
                            5 => "J&#46; Gertsch"
                          ]
                        ]
                      ]
                    ]
                  ]
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                        "volumen" => "22"
                        "paginaInicial" => "15"
                        "paginaFinal" => "22"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/21377114"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
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              "identificador" => "bib0270"
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                      "titulo" => "Prevention of acute mountain sickness by dexamethasone"
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                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "T&#46;S&#46; Johnson"
                            1 => "P&#46;B&#46; Rock"
                            2 => "C&#46;S&#46; Fulco"
                            3 => "L&#46;A&#46; Trad"
                            4 => "R&#46;F&#46; Spark"
                            5 => "J&#46;T&#46; Maher"
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                      ]
                    ]
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                        "tituloSerie" => "N Engl J Med"
                        "fecha" => "1984"
                        "volumen" => "310"
                        "paginaInicial" => "683"
                        "paginaFinal" => "686"
                        "link" => array:1 [
                          0 => array:2 [
                            "url" => "https://www.ncbi.nlm.nih.gov/pubmed/6700643"
                            "web" => "Medline"
                          ]
                        ]
                      ]
                    ]
                  ]
                ]
              ]
            ]
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              "etiqueta" => "55"
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                0 => array:2 [
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                    0 => array:2 [
                      "titulo" => "Glucocorticoids as prophylaxis against acute mountain sickness"
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                        0 => array:2 [
                          "etal" => false
                          "autores" => array:6 [
                            0 => "M&#46; Basu"
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                            2 => "S&#46; Kumar"
                            3 => "K&#46; Pal"
                            4 => "R&#46; Prasad"
                            5 => "W&#46; Selvamurthy"
                          ]
                        ]
                      ]
                    ]
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                    0 => array:1 [
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                        "tituloSerie" => "Clin Endocrinol"
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                        "paginaInicial" => "761"
                        "paginaFinal" => "767"
                      ]
                    ]
                  ]
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                            3 => "J&#46; Onopa"
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                        ]
                      ]
                    ]
                  ]
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                        "volumen" => "328"
                        "paginaInicial" => "797"
                      ]
                    ]
                  ]
                ]
              ]
            ]
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                          "etal" => false
                          "autores" => array:4 [
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                    ]
                  ]
                ]
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                        "link" => array:1 [
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Article information

ISSN: 21735808
Original language: English

DOI:10.1016/j.nrleng.2012.04.021

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Year/Month	Html	Pdf	Total

2024 November	18	2	20
2024 October	345	24	369
2024 September	452	32	484
2024 August	393	16	409
2024 July	391	16	407
2024 June	252	8	260
2024 May	256	13	269
2024 April	329	12	341
2024 March	393	14	407
2024 February	398	14	412
2024 January	355	16	371
2023 December	256	10	266
2023 November	295	16	311
2023 October	260	15	275
2023 September	204	17	221
2023 August	94	6	100
2023 July	99	8	107
2023 June	96	12	108
2023 May	152	14	166
2023 April	119	8	127
2023 March	112	8	120
2023 February	85	15	100
2023 January	83	12	95
2022 December	74	19	93
2022 November	71	12	83
2022 October	75	27	102
2022 September	51	37	88
2022 August	47	11	58
2022 July	50	18	68
2022 June	25	17	42
2022 May	25	13	38
2022 April	29	7	36
2022 March	86	17	103
2022 February	39	15	54
2022 January	72	9	81
2021 December	38	17	55
2021 November	42	11	53
2021 October	15	22	37
2021 September	20	17	37
2021 August	24	12	36
2021 July	22	11	33
2021 June	17	10	27
2021 May	46	19	65
2021 April	115	50	165
2021 March	75	53	128
2021 February	55	18	73
2021 January	31	17	48
2020 December	21	15	36
2020 November	16	7	23
2020 October	28	19	47
2020 September	21	14	35
2020 August	21	8	29
2020 July	39	20	59
2020 June	19	12	31
2020 May	208	20	228
2020 April	40	13	53
2020 March	37	11	48
2020 February	35	10	45
2020 January	26	5	31
2019 December	35	6	41
2019 November	17	13	30
2019 October	49	18	67
2019 September	51	17	68
2019 August	21	8	29
2019 July	29	10	39
2019 June	55	54	109
2019 May	88	46	134
2019 April	52	22	74
2019 March	36	16	52
2019 February	36	21	57
2019 January	27	20	47
2018 December	23	15	38
2018 November	31	19	50
2018 October	54	38	92
2018 September	40	17	57
2018 August	15	16	31
2018 July	12	7	19
2018 June	13	11	24
2018 May	14	13	27
2018 April	17	11	28
2018 March	28	11	39
2018 February	21	10	31
2018 January	19	14	33
2017 December	13	14	27
2017 November	24	7	31
2017 October	35	16	51
2017 September	22	8	30
2017 August	28	8	36
2017 July	22	12	34
2017 June	34	15	49
2017 May	30	25	55
2017 April	20	18	38
2017 March	18	23	41
2017 February	25	9	34
2017 January	38	13	51
2016 December	32	14	46
2016 November	42	13	55
2016 October	34	10	44
2016 September	34	16	50
2016 August	30	10	40
2016 July	32	8	40
2016 June	39	10	49
2016 May	18	19	37
2016 April	33	33	66
2016 March	30	37	67
2016 February	33	25	58
2016 January	24	23	47
2015 December	26	21	47
2015 November	47	27	74
2015 October	47	37	84
2015 September	38	34	72
2015 August	40	30	70
2015 July	36	6	42
2015 June	28	14	42
2015 May	87	36	123
2015 April	51	42	93
2015 March	65	37	102
2015 February	94	40	134
2015 January	111	38	149
2014 December	97	35	132
2014 November	64	33	97

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