Drug delivery by inhalation to administer bronchodilators and antiinflammatory medication has contributed significantly to improvements in care for patients with asthma. Inhalation therapy has been known and used for about 4000 years,1 although it was not until 1829 that the first device for producing particle suspensions was developed.2 In subsequent years a number of systems were perfected, and the first pressurized canister system was marketed in 1956.3 Spacers first appeared in the 1970s, and dry powder inhalers made their appearance soon after.3
Inhalation devices have made it possible to deliver very small doses of drugs directly to the target organ, thus achieving rapid, effective action with a minimum of side effects. Thanks to these systems, asthma can be controlled with highly effective treatments and minimal side effects, and patients can lead a completely normal life.
As shown in a number of studies4-6 and confirmed in this issue by Flor Escriche et al, patients use inhalation systems incorrectly, and this probably diminishes the efficacy of treatment. The authors found that 53.9% of their patients performed inhalation techniques incorrectly, the steps with the highest percentage error rates were exhaling completely before inhaling the dose, holding the breath after inhaling, and exhaling slowly afterwards.
Since the appearance of pressurized canisters, many other systems have appeared that aim to facilitate compliance with treatment, and that have been shown to increase the amount of drug that reaches the lungs. But this variety of products, each of which requires a different technique for correct use, confuses our patients and make compliance difficult. Flor Escriche et al document this in their study; moreover, they note that at any given time a patient may be using two or three different inhalation devices.
How can we improve our patients' inhalation technique? Do the kinds of errors in technique identified thus far have a clinically significant effect on the control of asthma? As I understand the issue, these are the questions that need to be answered, and the lines of research that could be undertaken:
To improve inhalation techniques, health education is needed both for health care professionals and for patients. Workshops should train health care professionals in the techniques used for different devices, the advantages of each, and in how to choose the most appropriate type of inhaler for different patients. These workshops should be held periodically; training the trainers is fundamental. As for the patients, their inhalation technique should be checked when they come to the health center, and errors in technique should be corrected. It is also important to use only one inhalation device for each patient.
Continuing quality improvement is based on a cycle consisting of several stages. First the problem must be detected (incorrect inhalation technique), then its possible causes analyzed (inadequate information about the correct technique, use of different devices, etc.). The next step is to plan corrective measures (workshops for professionals, checking inhalation technique at each visit, etc.), and this should be followed by further studies to determine whether the problem has been dealt with effectively.
With the technology currently available, health care professionals have access to a great deal of information in the form of guidelines, protocols, scientific journals, and other sources that help us to keep our knowledge up to date. These resources also help us to make the best diagnostic and therapeutic decisions for our patients. Articles such as that by Flor Escriche et al warn us that the recommendations in guidelines are not always followed. Therefore we should examine the possibility of incorporating in our daily work processes a system of practice audits as part of a continuing quality improvement program.
