Comparing Infection Rates from Using Different Surgical Preparation Solutions and Techniques in Foot & Ankle Elective Surgery

Abstract

Category: Other Introduction/Purpose: Surgical site infection (SSI) after Foot & Ankle surgery ranges from 1.2% to 13.2%, higher than any other elective orthopaedic procedure. Infection is of concern for the patient and expensive for the healthcare system. SSI is multifactorial and can be divided into host-related and perioperative factors. Skin preparation is one of the key peri-operative factors in reducing SSI. The current literature supports a combined chlorhexidine and alcohol preparation technique, although there is some conflicting evidence. Most studies to date have used proxy outcomes such as growth from swabs shortly after skin preparation. There are no large scale studies which have looked at definitive clinical outcomes such as the rate of postoperative SSI. Methods: A retrospective review of data was undertaken for two longitudinal cohorts which were using two different skin preparation solutions and techniques due to a change in hospital protocol. Each cohort was continuous and derived from the same overall populationIn cohort 1, Povidine-Iodine (Betadinetm) followed by Alcoholic Chlorhexidine was used on swabs (Double prep group). In cohort 2, 2 Alcoholic Chlorhexidine was used in a prep stick applicator. Standard criteria for diagnosing surgical site infection were used. All open injuries, procedures for ongoing infection, amputations for osteomyelitis /diabetic foot and COVID- 19 positive cases were excluded. Results: After applying standard exclusion criteria, 919 elective F&A procedures in the Double prep group and 491 procedures were included for the Single prep groupAs these were continuous longitudinal cohorts of large scale from the same population, there is a justifiable presumption of group matchingIn cohort 1 there were 15 superficial infections (1.6%) and 3 deep (0.3%). In cohort 2 there were 18 superfical infections (3.6%) and 1 deep (0.3%). The total infections in cohort 1 were 18 (2%) and 19 in cohort 2 (3.9%)There was an increase in superficial, and therefore total infection rates, in the single prep group compared to the double prep group. These increases were statistically significant; p <0.05 with regards to superficial infection and total infection rates in the single prep group. Conclusion: Double skin preparation, with Povidone-Iodine followed by alcoholic Chlorhexadine, statistically significantly decreases foot and ankle surgical infection rates as compared to a single alcoholic chlorhexidine skin preparation