Development and validation of rapid use scope test strips to determine the efficacy of manual cleaning for flexible endoscope channels

Background: Cleaning of flexible endoscopes is most commonly performed using manual methods that are often performed inadequately. The aim of this study was to validate the sample collection protocol and the Rapid Use Scope Test (RUST) and then assess its usefulness in clinical use. Methods: The benchmarks for adequate cleaning were protein <6.4 μg/cm², hemoglobin <2.2 μg/cm², and carbohydrate <1.2 μg/cm ². Sample collection consisted of flushing 10 mL of sterile reverse osmosis water through the suction-biopsy port to the distal end. Validation of the RUST audit tool included simulated-use and in-use testing in 43 endoscopy clinics across Canada. Results: Simulated-use testing validated that improperly cleaned endoscopes that exceeded the cleaning benchmarks would be flagged by the RUST test. The clinical-use study indicated that 96.6% of 1,489 scope channels tested were RUST negative; however, 19% and 12% of elevator guide-wire channels and endoscopic retrograde colangiopancreatography channels, respectively, exceeded the benchmarks. The survey indicated that reprocessing personnel valued a rapid audit tool for assessing compliance with manual cleaning. Conclusion: The validated RUST test provides health care users with a rapid audit tool for manual cleaning that can be integrated into the quality program in endoscopy.