This was a single-center observational study. A total of 328 outpatients scheduled for simultaneous EGD and colonoscopy and following a split-dosing or previous-day regimen of SPMC were included. We prospectively measured colon cleanliness by using the Ottawa Bowel Preparation Scale, RGFV, and RGFpH.
Ottawa Bowel Preparation Scale scores for overall, right, mid-colon, and colon fluid were significantly better in the split-dosing group. In the split-dosing group, the 3- to 4-hour fasting time consistently achieved the best cleansing quality. RGFV was significantly lower in the split-dosing group (11.09 vs 18.62, P < .001). No significant differences in RGFpH were detected.
Split-dosing SPMC provides higher colon cleansing quality with lower RGFVs than previous-day SPMC regimens. SPMC in split-dosing acts exactly as a standard clear liquid acts, and thus anesthetic guidelines on this issue may be applied with no concerns.