[Effectiveness of 9 soaps and/or antiseptics on hand flora after surgical-type washing]

Abstract

We studied the effect of nine soaps and/or antiseptics on the bacterial flora of hands 5 minutes after a surgical scrub. Each agent was used by ten healthy volunteers, free of skin lesions. The following agents were used: chlorhexidine gluconate 4% and 1.5%, povidone iodine 4%, ethanol 70 degrees, isopropanol 70 degrees, a non-antiseptic soap, and another soap followed by either ethanol 70 degrees, isopropanol 70 degrees or a preparation containing H2O2. The surgical scrub procedure varied slightly according to whether or not the agent was soapy and required rinsing. Sampling was carried out using Gaschen's bag method with 400 ml of neutralising solution. Counts were made after 48 hours aerobic incubation at 35 degrees C on tryptic soy agar with 1% Tween 80, and after 8 days anaerobic incubation at 35 degrees C on Brewer's yeast agar with 1% Tween 80. Results were expressed as the log 10 to the number of bacteria per hand. Statistical significance was determined using the Student t test. The greatest reduction in aerobic flora was produced by isopropanol 70 degrees C (1.7 log 10). 1.5 to 0.5 log 10 reductions were produced, in the following decreasing order, by ethanol 70 degrees, povidone iodine, chlorhexidine gluconate 4% and 1.5% and a soap with ethanol 70 degrees. A reduction of less than 0.5 log 10 was produced by a soap with isopropanol 70 degrees, and soaps with H2O2. Similar results were obtained with the facultative anaerobes.