Risk factors for surgical site infection after dermatological surgery

Abstract

Surgical site infection (SSI) following minor surgery contributes to patient morbidity and compromises cosmetic outcomes. The purpose of this study was to determine the incidence of and risk factors for SSI after dermatological surgery in general practice. A prospective, observational study which assessed infection among 972 patients was conducted in regional north Queensland, Australia. Consecutive patients presenting for minor skin excisions were invited to participate. Wounds were assessed for SSI at the time of removal of sutures. Infection occurred in 85 of the 972 excisions; thus, the overall incidence of infection was 8.7% (95% confidence interval 6.5-11.0). Excisions in the upper (P<0.001) or lower (P<0.001) extremities, excisions of basal cell carcinoma (BCC) (P=0.001) or squamous cell carcinoma (SCC) (P=0.001), and re-excision of skin cancer were found to be independent risk factors for wound infection. The length of the excision (P<0.001) and the patient's status as an ex-smoker (P=0.019) were additional independent risk factors for infection. Diabetes was not found to be an independent risk factor for infection (P=0.891). Prophylactic antibiotics are probably prescribed excessively or inappropriately for dermatological surgery, and overall we wish to discourage their use. The results of this study may encourage the more judicial use of prophylactic antibiotics by defining high-risk procedures, such as excisions from the extremities, excision of BCC or SCC, and larger excisions, and patients who are at high risk for infection, such as ex-smokers.