Whaley, Renee

Objectives: Surgical site infections (SSIs) are the most common hospital-acquired infections in the United States, of which methicillin-resistant Staphylococcus aureus (MRSA) accounts for 43%. Preoperative povidone-iodine nasal swab (PNS) is considered an effective and cost-saving treatment for Staphylococcus aureus decolonization. We aim to assess the impact of preoperative PNS on SSI incidence. Materials and Methods: This retrospective observational study utilized elective surgical cases between January 1, 2018 and May 31, 2023, at a single academic medical center. The cohort was divided into PNS and no PNS groups. The cohort was propensity-matched, and Pearson χ2/Kruskal-Wallis tests were performed to compare group differences. Multivariable logistic regression was utilized to compare events between cohorts before and after matching. An alpha of <0.05 was considered significant. Results: A total of 45,998 (22,999 per group) matched participants were evaluated. On multivariate regression, the non-PNS treatment group was associated with an increase in hospital overall SSI occurrence (OR: 1.48, P = 0.02) but not specifically in-hospital methicillin-sensitive Staphylococcus aureus SSI, MRSA-SSI, or any 30-day SSI (P > 0.05). Compared with PNS treatment and prophylactic antibiotics, in-hospital SSI was higher in the absence of PNS treatment (OR: 1.83, P < 0.001), antibiotic (OR: 2.63, P < 0.001), or both (OR: 2.06, P < 0.01). Compared with PNS treatment plus prophylactic antibiotic, in-hospital MRSA-SSI was only higher in the absence of antibiotic (OR: 2.92, P < 0.01) treatment. Conclusions: Preoperative treatment with PNS may reduce overall in-hospital SSI but has no independent impact on MRSA SSI.