The outcome of a second preparation for colonoscopy after preparation failure in the first procedure

BackgroundThere are scant data regarding the outcome of consecutive repeated procedures in patients who failed to adequately clean their colon for colonoscopy.ObjectiveTo investigate the outcome of a second colonoscopy after preparation-associated failure of the first colonoscopy.Design and SettingA retrospective study in a tertiary-referral center.PatientsAll patients with failure of colonoscopy because of poor preparation within a 1-year period.ResultsOf a total of 6990 colonoscopies performed during the study period, 307 procedures (4.4%) failed because of inadequate preparation. Data on subsequent repeated colonoscopies were available for 235 patients. The repeated procedure again failed because of unsatisfactory preparation in 54 of these patients (23%). The failure rate in subsequent third and fourth colonoscopies was also high (more than 25%). Of the various patient and procedure-related parameters examined, only the use of calcium channel blockers (CCB) was found to be predictive of a failed repeated preparation (odds ratio [OR] 3.2 [95% CI, 1.6-6.3], P < .001). In contrast, a next-day colonoscopy after failure of the index procedure was associated with a reduced risk of unsatisfactory second preparation (OR 0.31 [95% CI, 0.1-0.92], P = .03).LimitationsValidated data on the specific bowel purgatives used were not available.ConclusionsAlmost a fourth of patients with an unacceptable colonic preparation will also fail the repeated colonoscopy, and patients who use CCB are at particular risk for failure. Strategies to manage this difficult-to-treat patient group should be investigated and may possibly include a preference for next-day colonoscopy.