Povidone-Iodine Versus Saline Irrigation on Reduction of Surgical Site Infections in Total Hip and Knee Arthroplasty: A Retrospective, Propensity-Matched Cohort

Introduction: Surgical site infection (SSI) after total hip and knee arthroplasty (THA/TKA) is a major complication leading to morbidity and mortality. Perioperative irrigation, frequently with antiseptic compounds including povidone-iodine (PI), is the standard of care in reducing SSI. Evidence supporting the value of PI versus nonantiseptic substances varies. This study aims to identify whether PI irrigation in THA/TKA reduces the rate of SSI versus normal saline irrigation. Patients and Methods: A retrospective, propensity-matched cohort study of patients who underwent TKA or THA was conducted using data from patient charts, hospital infection control surveillance software, and operative reports. SSI rates of patients who had received PI versus saline irrigation were compared. Patient medical status, demographics, and procedure details were considered for propensity score determination and matching. Results: The study encompassed 21,482 patients. The unadjusted univariate analysis demonstrated no statistically significant difference in SSI rate between PI and saline (p = 0.759). Multivariate analysis showed that men, patients with diabetes, and those with a 2-3 h procedure time had increased risk of SSI, but differences were not observed between irrigation groups. Propensity score matching yielded 21 (0.25%) SSI in the matched PI group and 19 (0.23%) in the saline group (odds ratio: 1.10; confidence interval: 0.59-2.06). Conclusions: This investigation proposes that PI irrigation is not significantly different to saline in reducing SSI in this population. When cost is of concern, saline irrigation is equally effective and therefore a sensible option.