Evaluation of a Modified Bowel Preparation Regimen in Cirrhotic Patients Undergoing Colonoscopy

Inadequate bowel preparation compromises colonoscopy quality and diagnostic accuracy, and cirrhosis is a recognized independent predictor of poor bowel cleansing. However, no bowel preparation regimen has been prospectively validated or specifically tailored for cirrhotic patients.

This multicenter, prospective, randomized, single-blind controlled clinical trial will evaluate whether the addition of adjunctive measures as an intensified bowel preparation protocol improves bowel cleansing quality in adult patients with cirrhosis undergoing elective outpatient colonoscopy.

Participants will be randomized 1:1 to receive either a standard bowel preparation protocol, consisting of a 2-litre split-dose polyethylene glycol (PEG) regimen combined with a one-day low-residue diet and clear liquids the afternoon before the procedure (control), or the same split-dose regimen with the assigned adjunctive measures: 15 mg bisacodyl, a 3-day low-residue diet, and clear liquids the day before colonoscopy (intervention).

The primary outcome is the proportion of patients achieving adequate bowel preparation, defined as a Boston Bowel Preparation Scale (BBPS) total score ≥6 with no individual segment score \<2. Secondary outcomes include polyp, adenoma, advanced adenoma and colorectal cancer detection rates, caecal intubation rate, patient compliance, tolerability, and adverse events. Pre-specified subgroup analyses will evaluate the influence of etiology and severity of cirrhosis and portal hypertension complications.

By addressing a critical and unmet clinical need, this trial aims to generate high-quality evidence to optimize bowel preparation strategies in patients with cirrhosis, improve colonoscopy quality, and ultimately enhance colorectal cancer screening outcomes in this vulnerable population.