Antibiotic prophylaxis in inguinal hernia surgery

We read with great interest the consensus document recently published in your journal about antibiotic prophylaxis in surgery. The full text of the hernia section of that consensus document refers to risk factors for surgical site infection (SSI), and recommends their use “if there are risk factors such as relapse, advanced age, immunosuppression, drains or if prolonged operative duration is anticipated.” However, the authors conclude that “given the difficulty of predicting some of the risk factors in the preoperative period, prophylaxis is recommended in open groin herniorrhaphy and hernioplasty.”¹

We believe that risk factors related to hernia (bilateral or recurring) are diagnosed in practice through physical examination and recorded in the medical history and, in particular, the type of hernia should be coded in the surgery request registry before patients are added to surgery waiting lists at hospitals.

The latest International Guidelines for Groin Hernia Management indicate that there are few data for drawing conclusions on the usefulness of antibiotic prophylaxis with patients with immunosuppression or diabetes. However, in settings/regions where the infection rate is high, its use is recommended.²

Spain is considered a high surgical risk region² along with Pakistan, Turkey, parts of India and Japan. This designation is rooted in an inconclusive study conducted by Celdran et al.³ in 2004 with 100 patients, which was suspended due to the high rate of infection in the placebo group (8.1%) versus the absence of infection in the group that received prophylaxis with cefazolin, with differences approaching significance (p = 0.059). However, studies such as the one conducted by Morales et al.⁴ in 2000, using a single antibiotic in a randomised, double-blind clinical trial with a total of 524 patients, were unable to demonstrate that administration of antibiotic prophylaxis protected against the development of SSI, even though they considered it necessary to stratify patients by surgical risk and avoid the generalised use of antibiotics.

In 2003, Romero et al.⁵ conducted an interventional study in 425 non-randomised patients that compared cefuroxime 1.5 g to placebo in primary or recurring groin hernia surgery. The control group made up of 218 subjects presented a rate of SSI of 0.45% (n = 1) versus the placebo group (n = 207) with an incidence of 0.48% (n = 1), with no statistically significant differences. Despite the study's lack of randomisation, the authors concluded that there was insufficient evidence for systematically recommending antibiotic prophylaxis in patients with no risk factors who are to undergo hernioplasty.

At the same time, Oteiza et al.⁶ published a randomised prospective study comparing preoperative administration of amoxicillin/clavulanic acid 2 g versus a group with placebo. There was only one case of SSI in a patient who had received antibiotic prophylaxis, and no differences between groups were observed. Therefore, the authors did not support the use of antibiotic prophylaxis in groin hernia surgery when prosthetic material is used.

The latest Cochrane review, signed by Orelio et al., concluded that antibiotic prophylaxis in elective groin hernia surgery cannot be universally recommended. It likely reduces all types of infection (superficial and deep) in settings with a high risk of infection, but there are no differences or minimal differences in those with a low risk. In addition, it appears to have effect no (or minimal) preventive effect on deep infection, regardless of the setting.⁷

For all of the above reasons, we believe that the generalised use of prophylaxis in open groin hernia surgery will lead to overuse of antibiotics. Given that the risk factors discussed (bilateral or recurring hernia and advanced age) can be readily identified in a patient's medical history, it is possible to reduce its use and thus decrease costs, risks for the patient (possibility of adverse reactions or anaphylaxis and Clostridium difficile infection) and the selection of resistant micro-organisms.^8,9