Cecal Intubation Time between the Use of One‐ and Two‐Channel Water Exchange Colonoscopy: A Randomized Controlled Trial

BACKGROUND AND AIM: Water exchange (WE) colonoscopy is the least painful insertion technique with high adenoma detection rate but requires a longer intubation time. In the published literature, some investigators used the instrument channel for both infusing and suctioning of water (one channel), while others use colonoscopes with an integrated water-jet channel specifically designed for infusing water (two channel). The aim of this study was to compare cecal intubation time between one-channel and two-channel WE. METHODS: A total 120 patients undergoing colonoscopy from May 2017 to April 2019 at a regional hospital in southern Taiwan were randomized to either a two-channel group (n = 60) or a one-channel group (n = 60). The primary outcome was cecal intubation time. RESULTS: The mean cecal intubation time was significantly shorter in the two-channel group compared with the one-channel group (14.0 +/- 4.0 vs 17.4 +/- 6.7 min, P < 0.001). The two-channel group required less water infused during insertion (564.8 +/- 232.4 vs 1213.3 +/- 467.5 mL, P < 0.001) but achieved a significantly higher Boston Bowel Preparation Scale score (8.4 +/- 0.8 vs 7.5 +/- 1.1, P < 0.001) than did the one-channel group. The adenoma detection rate was comparable in the two groups (50.0% vs 48.3%, P = 0.855). CONCLUSIONS: In comparison with the one-channel WE, two-channel WE showed a shorter cecal intubation time, required less amount of water during insertion, and provided a better salvage cleansing effect. (NCT03279705).