Up to 25% of all bowel preparations for colonoscopy are considered inadequate. What bowel cleansing regimen should be used for these patients with previous inadequate bowel preparation? In a study by Gimeno-Garcia et al published by the American Journal of Gastroenterology, patients with inadequate cleansing at index colonoscopy were randomized to 4-L split-dose polyethylene-glycol (PEG) regimen vs. 2-L split-dose PEG plus ascorbic acid (PEG+Asc) regimen. All individuals underwent a 3-day low-residue diet and received 10 mg of bisacodyl, the day before colonoscopy. Cleansing was considered to be adequate if the Boston Bowel Preparation Scale scored≥2 at each colonic segment.

Adequate bowel cleansing was significantly higher in patients randomized to 4L PEG regimen vs. those randomized to 2L PEG+Asc regimen (81.1% vs. 67.4%).  There was no difference between the 2 groups on withdrawal time, polyp detection rate or adenoma detection rate.

This study is the first randomized study to examine bowel cleansing regimen in patients with previous inadequate bowel preparation.

How to use the regimen:

3 days before colonoscopy: Low residue (low fiber) diet

2 days before colonoscopy: Low residue (low fiber) diet

1 day before colonoscopy: Low residue (low fiber) diet

2 tablets of Bisacodyl (10mg)  at 19:00 hours

2 Liters of PEG-based agent (Colyte, Golytely, NuLYTELY, or TriLyte) at 20:00 hours

Day of colonoscopy: 2 Liters of PEG-based agent (Colyte, Golytely, NuLYTELY, or TriLyte)  4 hours before scheduled colonoscopy.

 

Reference: Gimeno-Garcia et al. Comparison of Two Intensive Bowel Cleansing Regimens in Patients With Previous Poor Bowel Preparation: A Randomized Controlled Study. Am J Gastroenterol advance online publication, 14 March 2017; doi: 10.1038/ajg.2017.53   .