Evaluation of the antiseptic activity of 5% alcoholic povidone-iodine solution using four different modes of application: a randomized open-label study

Background: Before some invasive procedures, such as injections, surgical incision or intravascular catheter insertions, alcoholic antiseptics (e.g., alcoholic povidone-iodine (PVP-I)) are widely used to prevent infection. Aim: This randomized, open-label study investigated the impact of mode of application (which includes both application technique and volume) on the antiseptic activity of 5% alcoholic PVP-I solution. Methods: Alcoholic PVP-I was administered to the backs of healthy adults using four modes of application: (A) concentric circle method, 3 mL; (B) concentric circle method, 10 mL; (C) back-and-forth friction method, 3 mL; (D) back-and-forth friction method, 10 mL. Primary endpoint: antiseptic activity of alcoholic PVP-I, assessed via change from baseline in log(10)/cm(2) colony-forming units (cfu) count for total aerobic and facultative anaerobic bacteria. Safety was monitored. Findings: A total of 113 healthy participants were screened; 32 were randomized. Alcoholic PVP-I showed significant antiseptic activity with all modes of application (P<0.001 for each), providing an overall mean decrease from baseline in cfu count of >3 log(10)/cm(2) (P<0.001). Significantly greater efficacy was seen with back-and-forth friction (modes C and D) versus concentric circles (modes A and B): covariate adjusted change in log(10)/cm(2) cfu count 0.22; 90% confidence intervals: 0.07, 0.37 (P=0.017). No safety issues were observed. Conclusions: Alcoholic PVP-I demonstrated high antiseptic activity for all modes of application. Greater efficacy was achieved with back-and-forth friction versus concentric circles, showing that application technique may influence antiseptic activity; these findings suggest that when comparing the efficacy of antiseptic substances (e.g., alcoholic PVP-I and alcoholic chlorhexidine), comparable application techniques should be used. (C) 2022 The Authors. Published by Elsevier Ltd on behalf of The Healthcare Infection Society.

Automated summary

This study investigated the impact of different application techniques on the antiseptic activity of alcoholic povidone-iodine solution. The results showed significant antiseptic activity with all modes of application, and greater efficacy was achieved with back-and-forth friction method compared to concentric circle method. These findings suggest that application technique may influence antiseptic activity, and comparable application techniques should be considered when comparing the efficacy of different antiseptic substances.