A randomized, controlled trial comparing air insufflation, water immersion and water exchange during minimally sedated colonoscopy - an interim report.

Background: Water-aided methods for colonoscopy are distinguished by timing of removal of infused water, predominantly during withdrawal (water immersion, WI), or during insertion (water exchange, WE). Objective: In a prospective randomized controlled trial (RCT) we assessed the hypothesis that compared with air insulation (AI), We produces significantly greater reduction in insertion pain than WI. Methods: The study was approval by local IRB and registered (NCT0090555). 200 patients were allocated into 3 groups by computerized randomization. AI, WI and WE were implemented as previously described. In all groups, during the insertion phase of colonoscopy, a study nurse asked the patient to report the level of pain (0=none, 10=most severe) at 2 to 3-min intervals or at any time the patient voiced discomfort. During the withdrawal phase, the pain was recorded in a similar manner. procedural outcomes were recorded. Results: Demographic variables and final cecal intubation rates were comparable. compared with AI, WI and WE both produced significantly better bowel preparation scores during colonoscope withdrawal and significantly lowered pain scores (AI 3.8±3.0, WI 2.4±2.6, WE 1.5±2.4, p<0.001) during colonoscope insertion. compared with AI, We produces significantly greater reduction in insertion pain than WI. The cecal intubation time was the longest in the We group (AI vs. WI vs. WE, 8.9±7.3, 6.6±3.6 and 17.5±6.4 min, p<0.001) Conclusion: Both WI and WE significantly reduced insertion pain compared with AI. Water exchange is superior to water immersion in attenuating insertion pain. [ABSTRACT FROM AUTHOR]