A Randomized Controlled Trial Comparing Colonoscopic Enema With Additional Oral Preparation as a Salvage for Inadequate Bowel Cleansing Before Colonoscopy.

GOALS: The goal of this study was to evaluate the noninferiority of colonoscopic enema to additional oral preparation in salvage bowel cleansing for inadequate preparation for a morning colonoscopy.

BACKGROUND

Colonoscopic enema, administering additional cathartics into the right colon through the colonoscope accessory channel, is suggested to rescue poor bowel preparation for a colonoscopy but lacking comparative study.

STUDY: In this prospective, randomized, actively-controlled, parallel group, noninferiority trial, consecutive outpatients and health checkup recipients aged from 19 to 70 years with inappropriate bowel preparation during an elective colonoscopy were enrolled to receive either a colonoscopic enema of 1 L polyethylene glycol (PEG) (enema group) or additional oral intake of 2 L PEG (oral group). The primary endpoint was the proportion of adequate bowel preparation evaluated using the Boston Bowel Preparation Scale.

RESULTS

Overall, 131 participants were randomized. Adequate bowel preparation was achieved in 53% (35/66) of the enema group, which was significantly inferior to the oral group (81.5%; 53/67) with a difference of -28.5% (95% confidence interval, -44.1, -12.9; P=0.001). The largest difference in the proportion of adequate bowel preparation was observed in the right colon (57.8% in the enema group vs. 86.9% in the oral group; P<0.001), followed by the transverse colon (85.9% vs. 98.4%; P=0.017) and the left colon (90.6% vs. 96.7%; P=0.274).

CONCLUSIONS

The colonoscopic enema of 1 L PEG was inferior to the additional oral ingestion of 2 L PEG regarding efficacy as a salvage bowel preparation in adults with inadequate bowel cleansing for colonoscopy.