Impact of a novel water method on scheduled unsedated colonoscopy in U.S. veterans

Background: Intermittent warm-water infusion in lieu of air insufflation permitted 52% of patients who accepted sedation on demand to complete colonoscopy without sedation. Objective: To test the hypothesis that the water method enhances cecal intubation and increases the proportion of patients who report willingness to repeat a scheduled unsedated colonoscopy. Design: Observational study. Patients: Two consecutive groups of veterans. Interventions: From June 2005 to May 2006, the usual air insufflation method was used to aid colonoscope insertion. From June 2006 to October 2007, the water method was used. Main Outcome Measurements: Cecal intubation; report of willingness to repeat unsedated colonoscopy. Results: Sixty-two and 63 veterans were examined by the air method and the water method, respectively. Intention-to-treat analysis revealed that the cecal intubation rate with the water method (97% [61/63]) was significantly higher than that with the air method (76% [47/62]). The proportion of patients who reported willingness to repeat unsedated colonoscopy was significantly higher with the water method (90% [57/63]) compared with the air method (69% [43/62]). Limitations: Single site, nonrandomized, unblinded, small number of elderly male veterans. Conclusion: The effects of the water method in the group for scheduled unsedated colonoscopy were sufficiently provocative to warrant calling for their confirmation by a randomized controlled trial.