Tu1106 STEAM STERILIZATION DECREASES CONTAMINATION OF FLEXIBLE GASTROINTESTINAL ENDOSCOPY'S VALVES : A PRACTICAL METHOD TO DECREASE ENDOSCOPY-RELATED IATROGENIC INFECTION

Abstract

Endoscopy-associated pathogen transmission has been recognized as an important issue of safety. Inadequate decontamination procedures and equipment malfunction are two leading causes of post-endoscopic infection and contamination. The current guideline suggests manual cleaning, followed by high-level disinfection(HLD) as standard reprocessing procedure. The FDA has highlighted the cross-contamination risk associated with valves(suction, air/water and biopsy valve) when used with flexible gastrointestinal endoscope accessory in 2018. Single-use valves are still in development, and the feasibility remains unclear due to cost-effectiveness. In this study, we evaluated the effectiveness of manual cleaning, and the feasibility of HLD followed by steam sterilization(SS) as a practical method in real-world for valve reprocessing to decrease contamination rate. All valves from the endoscopy were reprocessed by 3 steps. Manual cleaning was followed by HLD, and HLD was followed by SS. We performed manual cleaning in 2 situations, under and without supervision. We cultured the samples of valves from the endoscopy after each reprocessing step. The SS protocol was under 134°C-136°C and 31-32 pounds per square inch for 4 minutes. The samples for cultures were acquired from 1ml bottom layer fluid by using 40 ml sterile distilled water soaking valves, followed by vibration with a vibrating tester for 1 minutes and centrifugation under 3000rmp for 5 minutes. All samples were cultured under 35°C for 48 hours. 22 sets of cultures were obtained(8 sets under real-time supervision and 14 sets without supervision when manual cleaning). The positive culture rate was 77% after manual cleaning(63% under supervision and 86% without supervision), 32% after HLD(including 9% of false negative cultures which became positive after SS, 13% under supervision and 43% without supervision) and 18% after SS(0% under supervision and 29% without supervision). The positive high-concern organisms culture rate was 59% after manual cleaning(25% under supervision and 79% without supervision), 14% after HLD(including 5% of false negative cultures which became positive after SS, 13% under supervision and 14% without supervision) and 5% after SS(0% under supervision and 7% without supervision). The major high-concern organisms were Pseudomonas, Klebsiella and Enterococcus species. The cost of SS was around 0.1 USD for 1 valve in Taiwan. Adequate and well-qualified manual cleaning plays a central role in decontamination procedures. However, it seems not reliable in terms of the consistency in real-word practice. HLD followed by SS is superior to HLD alone, and it could reduce 33% contamination rate in this situation. If adequate manual cleaning can be ensured, it is possible to erase all the contamination by HLD followed by SS.