Reconsideration of iodine in wound irrigation: The effects on Pseudomonas aeruginosa biofilm formation

Objective: Chronic skin wounds are usually colonised with bacteria and subsequent infection may develop. Topical antiseptics are commonly used to control bacterial colonisation. The topical antiseptic, 1% polyvinylpyrrolidone-iodine (PVP-I), that is used on chronic open skin wounds remains controversial in the clinical setting because of its cytotoxicity. Here, we tested 1% PVP-I solution against saline to determine if it reduces bacterial count on the wound surface and within the tissue that may lead to wound reduction. Method: Open wounds that were created on the backs of Sprague Dawley rats were inoculated with Pseudomonas aeruginosa at the wound surface. Wounds were kept covered except for wound irrigation, two days post-wounding, wounds were irrigated daily using a 10ml syringe and spray tip. Results: Our results indicate that 1% PVP-I irrigation resulted in a reduced bacterial count on the wound surface and within the tissue compared with saline irrigation. The 1% PVP-I irrigation promoted wound re-epithelialisation compared with saline irrigation, but it did not reach significance. Conclusion: These results indicated that irrigation with 1% PVP-I was an effective way to reduce bacterial count on the wound surface, and allow the wound to progress to healing.