Comparing the in Vitro Efficacy of Commonly Used Surgical Irrigants for the Treatment of Implant-Associated Infections

Background: Implant-associated infections (IAIs) require aggressive debridement to eliminate microbial bioburden. The use of irrigants may improve microbial killing during debridement. This study compared the efficacy of surgical irrigants in vitro against Staphylococcus aureus alone and in combination with Candida albicans , in both planktonic and biofilm states. Methods: Full-strength Dakin’s solution, 0.35% povidone-iodine (PI), 10% PI, 3% hydrogen peroxide (HP), a 1:1 combination of 10% PI and 3% HP (PI + HP), Irrisept, XPERIENCE, Bactisure, and normal saline solution were tested. For planktonic testing, 1 × 10 6 colony-forming units (CFUs) of S. aureus and C. albicans were utilized, and biofilms were grown in these conditions on 0.8 × 10-mm titanium alloy Kirschner wires for 48 hours. Killing assays were performed using 5-minute dwell times. Success was defined by complete eradication of planktonic or biofilm CFUs. Results: PI + HP and Bactisure were the only irrigants to eradicate S. aureus in both planktonic and biofilm states. PI + HP was the only irrigant to eradicate polymicrobial S. aureus + C. albicans bioburden in both states. Conclusions: PI + HP and Bactisure were superior irrigants against S. aureus, eliminating it in planktonic and biofilm states. PI + HP was the only irrigant to eradicate polymicrobial S. aureus + C. albicans bioburden in both states. In vivo studies are needed to evaluate the clinical effectiveness. Clinical Relevance: Surgical irrigants have variable efficacy in eradicating microbes depending on their state of existence (planktonic versus biofilm). In this study, the most effective eradication of polymicrobial S. aureus + C. albicans bioburden was a 1:1 combination of 10% PI and 3% HP, which is of nominal cost.