Useful Bowel Preparation with Ultralow-Volume (500 mL) Polyethylene Glycol for Colonoscopy: A Retrospective Study

Adequate bowel preparation is indispensable for high-quality colonoscopy. We have developed an ultralow-volume (500 mL) polyethylene glycol (PEG) combined with other laxatives (sennoside, sodium picosulfate, and lactulose) and applied this regimen clinically to all patients with colonoscopy for 3 decades. This study aimed to assess the effectiveness of this ultralow-volume bowel preparation regimen.

This single-center, retrospective study analyzed data from consecutive outpatients who underwent colonoscopy between January 2022 and December 2022. All the patients took sennoside (24 mg) two nights before, sodium picosulfate (75 mg) one night before, and 500 mL of PEG with lactulose (58.5 g) on the day of examination. Cleaning efficacy was evaluated using the Boston Bowel Preparation Scale (BBPS). Adequate bowel preparation was defined as a total BBPS score ≥6, with all colon segments scoring ≥2.

Out of 862 patients with colonoscopy, 773 were eligible for this study, and the median age was 66 years. The adequate bowel preparation rate was 91.8% (710/773). Notably, the BBPS full score "9" was observed in 50.5% (390/773). The median cecal intubation time and examination time were 8 and 20 min, respectively. Only 3 patients vomited as a side effect. In the multivariate analysis, age ≥70 years, diabetes mellitus, and diverticula were significantly independent risk factors for inadequate bowel preparation.

Our established ultralow-volume (500 mL) PEG is safe and useful as a bowel preparation method.