Background: Because of its volume, adequate bowel preparation remains problematic in physically unfit patients.
Objective: This study aimed to compare a small-volume sodium picosulfate/magnesium citrate preparation with a 2-L ascorbic acid-enriched polyethylene glycol solution plus bisacodyl.
Design: This study has a noninferiority design, assuming that ascorbic acid-enriched polyethylene glycol solution plus bisacodyl is 70% efficacious in achieving an Ottawa score ≤7 and accepting a difference in success rate of <15% with a target enrollment of 146 patients per group.
Setting: This study was conducted in an outpatient department.
Patients: Patients referred for diagnostic colonoscopy were randomly assigned. Key exclusion criteria were severe kidney disease, ASA class ≥III, and hospital admission.
Intervention: Patients were randomly assigned to receive sodium picosulfate/magnesium citrate or ascorbic acid-enriched polyethylene glycol solution plus bisacodyl according to a split-dose regimen. Patients in the sodium picosulfate/magnesium citrate group received advice on the recommended 4-L fluid intake. Patients in the ascorbic acid-enriched polyethylene glycol solution plus bisacodyl group received 2 bisacodyl tablets 2 days before and advice on the additionally recommended 2-L fluid intake.
Main outcome measures: To assess bowel-cleansing adequacy, the Ottawa, Aronchick, and Boston scores were used. Colonoscopy quality measures were obtained. Safety was assessed for a 30-day follow-up period.
Results: Overall, 341 patients (169 men, mean age 57.0 years; BMI 26.2 kg/m) were included. Comorbidities were present in 76.2% of patients, and 75.4% of patients used medication. An adequate Ottawa score was obtained in 81.4% and 75.8% of patients receiving ascorbic acid-enriched polyethylene glycol solution plus bisacodyl and sodium picosulfate/magnesium citrate (difference of 5.6% (95% CI, -3.5 to -14.6; p = 0.023)), showing noninferiority of the sodium picosulfate/magnesium citrate therapy. Ottawa segmental scores were lower for sodium picosulfate/magnesium citrate in the right and transverse colon. In both groups, successful ileocecal intubation was achieved in 95%. No medication-related adverse events were reported.
Limitations: These results in a physically disabled ambulant population cannot be extrapolated to immobile, hospitalized patients.
Conclusions: Sodium picosulfate/magnesium citrate proved to be noninferior to ascorbic acid-enriched polyethylene glycol solution plus bisacodyl in efficacy and safety. Timing of the colonoscopy and addition of bisacodyl to sodium picosulfate/magnesium citrate warrants further consideration. See Video Abstract at http://links.lww.com/DCR/A461.