New method for assessing hand disinfection shows that pre-operative alcohol/chlorhexidine rub is as effective as a traditional surgical scrub

Background: Several studies have shown that rubbing hands with an alcohol/chlorhexidine solution provides equivalent microbial decontamination to a conventional surgical scrub using aqueous chlorhexidine. However, the authors believe that these studies have methodological flaws that limit their applicability to the operating theatre environment. As such, a method was developed to compare products in an everyday operating theatre environment using working operating theatre personnel. Aim: To determine whether or not an alcohol/chlorhexidine rub is as efficacious as a traditional surgical scrub using a novel method. Methods: Bacterial counts at baseline were collected from 20 anaesthetists using the glove juice method. Subsequently, with sequential exchange of sterile gloves, one hand underwent a 3-min scrub using 4% aqueous chlorhexidine, and the other hand underwent a 60-s rub with a 70% isopropyl alcohol/0.5% chlorhexidine solution. The residual bacterial count was collected for each hand after 30 min using the glove juice method. These counts were converted to log(10) values to compare the baseline counts of right and left hands, and efficacy between the treatment groups. Findings: Mean [+/- standard deviation (SD)] bacterial counts at baseline were (log10) 4.42 +/- 0.81 for left hands and 4.64 +/- 0.60 for right hands (P > 0.05). The mean (+/- SD) reduction from baseline was (log(10)) 1.45 +/- 0.50 for 4% chlorhexidine and 2.01 +/- 0.98 for alcohol/chlorhexidine (P > 0.05). Conclusion: An alcohol/chlorhexidine hand rub was found to be as efficacious as a traditional scrub after 30 min; this study differs from previous work as it was undertaken in a population of practising anaesthetists in their working environment. The McKenzie method allows baseline and study evaluations to be performed contemporaneously on the same individual. Each subject was his/her own control. This method offers a more clinically relevant way to compare disinfectant solutions than standard methods. Crown Copyright (C) 2014 Published by Elsevier Ltd on behalf of the Healthcare Infection Society. All rights reserved.