A randomized, controlled trial to confirm the beneficial effects of the water method on U.S. veterans undergoing colonoscopy with the option of on-demand sedation

Abstract

Background: Sedation for colonoscopy discomfort imposes a recovery-time burden on patients. The water method permitted 52% of patients accepting on-demand sedation to complete colonoscopy without sedation. On-site and at-home recovery times were not reported.

Objective: To confirm the beneficial effect of the water method and document the patient recovery-time burden.

Design: Randomized, controlled trial, with single-blinded, intent-to-treat analysis.

Setting: Veterans Affairs outpatient endoscopy unit.

Patients: This study involved veterans accepting on-demand sedation for screening and surveillance colonoscopy.

Intervention: Air versus water method for colonoscope insertion.

Main outcome measurements: Proportion of patients completing colonoscopy without sedation, cecal intubation rate, medication requirement, maximum discomfort (0 = none, 10 = severe), procedure-related and patient-related outcomes.

Results: One hundred veterans were randomized to the air (n = 50) or water (n = 50) method. The proportions of patients who could complete colonoscopy without sedation in the water group (78%) and the air group (54%) were significantly different (P = .011, Fisher exact test), but the cecal intubation rate was similar (100% in both groups). Secondary analysis (data as Mean [SD]) shows that the water method produced a reduction in medication requirement: fentanyl, 12.5 (26.8) μg versus 24.0 (30.7) μg; midazolam, 0.5 (1.1) mg versus 0.94 (1.20) mg; maximum discomfort, 2.3 (1.7) versus 4.9 (2.0); recovery time on site, 8.4 (6.8) versus 12.3 (9.4) minutes; and recovery time at home, 4.5 (9.2) versus 10.9 (14.0) hours (P = .049; P = .06; P = .0012; P = .0199; and P = .0048, respectively, t test).

Limitations: Single Veterans Affairs site, predominantly male population, unblinded examiners.

Conclusion: This randomized, controlled trial confirms the reported beneficial effects of the water method. The combination of the water method with on-demand sedation minimizes the patient recovery-time burden. (

Clinical trial registration number: NCT00920751.).