Comparison of equipment management and cleaning protocols for rigid sigmoidoscopy

Background: To provide outcome data relating to cleaning of rigid sigmoidoscopy equipment comparing commonly used techniques, allowing a framework for general guidelines for use in clinical practice. Methods: A total of 104 rigid sigmoidoscopies were performed in the rooms of two colorectal surgeons using standard techniques. A three-way randomization was performed adopting the following variables: enzymatic washing versus steam sterilization of the light head, disposable versus reusable bellows and use with versus without an air filter. Aerosol from each system was collected on agar plates, and review of colony count numbers was performed. Results: Gross faecal contamination of the rigid sigmoidoscope light head did not occur during any of the procedures. One plate grew a single-gram negative colony; all other contaminated plates showed environmental flora only. Reusable bellows in combination with an air filter showed lower mean colony counts (environmental flora) from the pre-procedure cultures as well as from the bellows' cultures. Conclusion: Enteric flora in this study was rarely aerosolized, and the use of an air filter may decrease this likelihood even further. There is no advantage in using disposable insufflation bellows when compared with the reusable type, allowing considerable cost saving. Washing the light head between procedures with enzymatic solution is a safe cheap and effective method of decontamination.