Original ArticleComparison of the Antimicrobial Effect of Chlorhexidine and Saline for Irrigating a Contaminated Open Fracture ModelPenn-Barwell, Jowan G. MRCS*,†; Murray, Clinton K. MD‡; Wenke, Joseph C. PhD†Author Information *Extremity Trauma-Bone Group, US Army Institute of Surgical Research, Fort Sam Houston, San Antonio, TX †Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, United Kingdom ‡Department of Medicine, Infectious Disease Service, Brooke Army Medical Center, Fort Sam Houston, San Antonio, TX. Reprints: Jowan G. Penn-Barwell, MRCS, Royal Centre for Defence Medicine, Birmingham, West Midlands B15 2SQ, United Kingdom (e-mail: [email protected]). Presented in part at the Annual Meeting of the Orthopaedic Trauma Association, San Antonio, TX, 2011. The authors report no conflict of interest. The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the US Department of the Army or the Department of Defense. Accepted July 27, 2012 Journal of Orthopaedic Trauma: December 2012 - Volume 26 - Issue 12 - p 728-732 doi: 10.1097/BOT.0b013e31826c19c4 Buy Metrics Abstract Objectives: The objective of this study is to compare antimicrobial effect of irrigation with chlorhexidine gluconate (CHG) to saline in an animal model. Methods: This study used a segmental defect rat femur model contaminated with Staphylococcus aureus and treated 6 hours after injury with debridement and irrigation with 60 mL of fluid delivered at low pressure. In study groups of 10 animals each, 3 concentrations of CHG (0.5%, 0.05%, and 0.005%) were used and a group irrigated with 0.05% CHG and then saline and a control group treated with saline only. After irrigation the wounds were closed, and the rats were recovered. Fourteen days later, bone and implants were harvested for separate microbiological analysis. Results: There was no statistical difference detected between the subsequent presence or quantity of bacteria after irrigation, with aqueous CHG at a range of concentrations comparing irrigation with saline alone. Conclusions: This study does not support the use of CHG as an irrigant. This may be due to the antibacterial effect of CHG being offset by the associated host tissue toxicity. Host tissue damage from high irrigation pressures and cytotoxic solutions has been shown to allow bacteria to thrive. We believe this is due to a “rebound” of bacteria growth in a wound bed containing small quantities of necrotic tissue damaged by CHG exposure. © 2012 Lippincott Williams & Wilkins, Inc.