Establishing the shelf life of flexible colonoscopes.

This study was designed to establish a shelf life for processed (peracetic acid) flexible colonoscopes and to demonstrate the adequacy of manual cleaning procedures. The study challenges current practice in Australia where endoscopes are routinely reprocessed prior to use if the endoscope has been sitting at least overnight. The design was a simulated study in the clinical environment and involved artificial contamination of a colonoscope, cleaning validation, and a time series analysis after processing with peracetic acid in a Steris System 1 processor and drying with 100% isopropyl alcohol. The main outcome measure was the presence of bacteria in the internal channels of the colonoscope after cleaning and at 24 and 168 hours after processing with peracetic acid. The findings suggest that colonoscopes may be left for up to 1 week before needing to be reprocessed before use, provided all channels are thoroughly reprocessed and dried, resulting in cost savings and reduced wear and tear on the instruments. The findings also demonstrate the impact of providing feedback to staff on a regular basis about the efficacy of their cleaning techniques.