Incontinence after colonoscopy--an unrecognized and preventable problem. A cross-sectional study from the Gastronet...

Colonoscopy requires insufflation of gas for visualization of the bowel wall. Worldwide, this is usually done using air. The aim of the present study was to assess the risk of postcolonoscopy incontinence, and to investigate whether insufflation of CO₂ instead of air may reduce this risk, since it is easily absorbed through the bowel mucosa.

This is a prospective multicenter study of colonoscopy patients undergoing bowel insufflation using air or CO₂. A successive series of colonoscopies were reported to a national quality assurance program in Norway between January and December 2009 from 21 endoscopy centers with varying insufflation practices. The study comprised 7812 patients aged 18 years or older who were referred for outpatient colonoscopy. Of these, 5015 underwent colonoscopy performed using air and 2797 colonoscopy using CO₂ insufflation.

Patient-reported incontinence up to 24 h after colonoscopy was compared using binary logistic regression analysis for the type of gas used for insufflation. The air and CO₂ patient groups were comparable with regard to age, sex, indication for colonoscopy, and sedation practice. Incontinence was reported by 336 out of 7812 patients (4.3%). Incontinence was significantly less frequent in the CO₂ group than in the air group [2.1% versus 5.5%; adjusted odds ratio (OR) 0.38; 95%CI 0.28-0.50; P < 0.001]. Female patients had a higher risk of incontinence than men (adjusted OR 1.77; 95% CI 1.39-2.24; P < 0.001).

About every 20th patient undergoing colonoscopy using standard air insufflation experiences postexamination incontinence. This proportion can be reduced by 60% by converting from air insufflation to insufflation with the absorbable CO₂.