Comparison of the effectiveness of painting and immersing techniques, in pre-operative foot disinfection with chlorhexidine

Abstract

Background: Pre-operative preparation of the foot is challenging due to the anatomy and the range of organisms found in this area . Different antiseptic solutions are in current use for the preparation of skin. The lechnique used to apply the antiseptic solution has also been shown to be relevant to the effective clearance of microbes from the foot in particular. Objectives: To compare the efficacy of painting chlorhexidine onto the foot and immersing the foot in a bag containing chlorhexidine, in pre-operative skin preparation. Methods Design: This was a case control study. Study population and Sampling: The study was carried out at the Kenyatta National Hospital, the main referral hospital in Kenya from 12'' August to 30'' September 2011. 25 individuals were recruited from our inpatient population and hospital staff, giving a total of 50 feet. Selection of subjects was by convenience sampling.

Data Collection Procedure: Each subject had one foot prepared with the bag technique and the other foot prepared with the painting technique. Allocation of the feet to either technique was done using a table of random numbers. Pre preparation swabs were collected from randomly selected feet to identify the amount of skin bacteria present. Microbial clearance for both techniques was then assessed by means of culture from swabs taken from both feet when dry.

Results: The results of the study show the technique of immersing the foot in a non-sterile bag to be more effective in microbial clearance than swabbing the foot with sterile gauze. In the painting technique, positive growth was obtained tram nail folds in 56% of samples and 28% of samples from web spaces.

With the bag technique growth was obtained from nail folds in 36% of samples and 12% of samples from web spaces, p-values 0.013 and 0.029 respectively. The sampled pre preparation swabs all grew bacteria.

Conclusions: Use of the bag technique with chlorhexidine was found to be an effective method of eliminating potential wound contaminants from the foot as a method of skin preparation prior to surgery.