Incidence and associated factors of surgical site infection in patients undergoing foot and ankle surgery: a 7-year cohort study

Abstract

Surgical site infections (SSI) constitute 31% of all hospital-acquired conditions, with ankle and foot surgical procedures showing an incidence of SSI ranging from 0.5% to 6.5%. This study aimed to assess the incidence of both superficial and deep surgical site infections in foot and ankle surgery, along with associated factors. Conducted as a retrospective cohort study, it included 2180 patients undergoing foot and ankle surgery in a private hospital between 2014 and 2020, encompassing elective and trauma cases. Outcome variables comprised SSI, while predictor variables encompassed sex, age, diabetes mellitus, systemic arterial hypertension, smoking, American Society of Anesthesiologists (ASA) score, and body mass index. Logistic regression models were employed to identify associations between study variables. The incidence of surgical site infections stood at 4% (83/2180), comprising a rate of 2.8% (57/2180) for superficial infections and 1.2% (26/2180) for deep infections. Smoking (OR 2.9, 95%CI 1.4–5.3) and ASA score >2 (OR 3.4, 95%CI 1.2–8.4) emerged as independent factors associated with surgical site infections. The group with deep infections exhibited higher proportions of smokers (p = 0.002), systemic arterial hypertension (p = 0.018), trauma surgery (p = 0.049), and an ASA score >2 (p = 0.011). Overall infection incidence in this cohort reached 4%, with trauma cases, smoking, hypertension, and an ASA score >2 independently linked to deep infections. Surgeons should be cognizant of these risk factors when managing prophylactic antibiotic regimens for patients.