Superiority of Split-Dose Bowel Preparations for Morning and Afternoon Colonoscopies: A Single Center Experience

Background: ASGE guidelines recommend SPLIT for afternoon colonoscopies and when feasible for morning procedures. We compared the effects of different bowel preparations given as SPLIT vs. SINGLE on the quality of bowel preparation. Methods: In a University Hospital, all adult outpatients undergoing colonoscopy were offered the opportunity to participate in this survey during September and October 2015. Patients undergoing both screening and non-screening colonoscopies were included. 611 of 1002 asked patients filled out a survey. The Boston Bowel Preparation Scale (BBPS) was used to rate the preparation. We added a third component that determined how much cleaning effort was required. Results: SPLIT preparation, using a clear liquid diet and ingestion of 75% or more of the preparation were all associated with a statistically significant quality of bowel preparation and less colon irrigation. The study compared SPLIT vs SINGLE regimens, revealing the superiority of SPLIT dosing regardless of the timing of the colonoscopy, the gender of patients or the type of preparation. Only 3.8% of patients receiving SPLIT dose had a poor preparation compared to 11% of poor preparation with SINGLE. The need for repeat colonoscopy due to poor preparation was 6.2%. Conclusion: Our study confirms the superiority of SPLIT and clear liquid diet for both morning and afternoon colonoscopies. There was no significant difference in the quality of bowel preparations between different solutions. We recommend SPLIT for all colonoscopies regardless of timing.