1466. Povidone-Iodine Irrigation versus Saline Irrigation for Reduction of Surgical Site Infections in Patients Undergoing Total Knee and Total Hip Arthroplasty: a large retrospective, propensity matched cohort study

Abstract

Abstract Background Surgical site infection (SSI) after total hip and total knee arthroplasty (THA/TKA) is a serious surgical complication. Perioperative irrigation with antiseptic compounds such as povidone-iodine have been used and are recommended by the World Health Organization and the Centers for Disease Control to reduce this risk. However, evidence supporting its superiority relative to non-antiseptic substances such as saline has been inconsistent. Therefore, we aim to identify if irrigation with povidone-iodine in THA/TKA reduces incidence of SSI in patients compared to saline irrigation. Methods In this retrospective, cohort study of 21,482 patients who underwent TKA or THA, we compared SSI rates between patients who received povidone-iodine irrigation and saline irrigation. Univariate and multivariable analyses were performed to identify risk factors for SSI. We also performed a propensity matched analysis. Each patient’s propensity for receiving povidone-iodine irrigation was calculated using select patient and surgical variables. Standardized mean differences were calculated to confirm reduction of potential confounding between the matched groups. Results There were 8,486 patients given saline irrigation and 12,996 patients given povidone-iodine irrigation (Table 1). In the univariate analysis, we did not identify a difference between povidone-iodine and saline (p = 0.76). Multivariate analysis showed diabetes, general anesthesia, and a procedure time of 2-3 hours increased risk of SSI, but povidone-iodine irrigation was not significantly different from saline (OR 1.1; CI 0.6-1.9) (Table 2). After propensity score matching there were 21 (0.25%) SSI in the povidone-iodine group and 19 (0.23%) in the saline group. Standardized mean differences were below 0.2 for all selected variables (Table 3). Odds of SSI were no different between the two matched groups (OR 1.1; CI 0.6-2.1).Table 1.Overview of patient and surgical variables by irrigation solution.Table 2.Multivariable analysis adjusted for age, sex, diabetes mellitus, anesthesia type, and procedure time. Showing odds of developing a surgical site infection.Table 3.Graph of standardized mean differences before and after matching. Blue dots represent unmatched cohort. Orange dots represent matched cohort. Table shows odds of developing a surgical site infection for the matched cohort. Conclusion Our analysis indicates no difference between povidone-iodine and saline irrigation in reducing SSI after THA/TKA. In situations where financial cost may be a factor in determining whether to use saline or povidone-iodine, we conclude that saline irrigation is equally efficacious and therefore a reasonable choice. Disclosures Eric Smith, MD, Conformis: Advisor/Consultant|Depuy: Advisor/Consultant