Factors influencing inpatient colonoscopy bowel preparation quality

Colonoscopy is highly sensitive for the visualization of the entire colon. Inpatient colonoscopies pose a special risk of poor preparation. We reviewed bowel preparation methods and patient factors to identify predictors of inadequate bowel preparation for inpatient colonoscopy at our institution. The purpose of this study was to identify factors that predict inadequate bowel preparation for inpatient colonoscopies.

All patients ages >18 years of age undergoing inpatient colonoscopy in 2017-2018 were reviewed. The primary outcome was inadequate bowel preparation and secondary outcomes were successful cecal intubation, duration of colonoscopy, and hospital length of stay (LOS). Outcomes were compared using multivariable regression with stepwise covariate selection.

The analysis included 315 patients (median age =67 years; 45% female). Visualization was deemed adequate in 56%, fair in 27%, and poor in 17% of cases. Cecal intubation was successful in 84% of cases. The median duration of colonoscopy was 25 min and LOS was 2 days. Unsuccessful cecal intubation was most likely with poor visualization compared to adequate visualization (36% vs. 11%, P=0.014). There was no increased colonoscopy duration with poor visualization (P=0.075). There was no significant LOS with worse visualization quality (P=0.185). Factors predicting worse visualization quality included older age, history of congestive heart failure (CHF), cirrhosis, and motility disorders.

At our institution, patients who were older or had significant comorbid conditions (chronic artery disease, CHF, chronic obstructive pulmonary disease, motility disorders, or cirrhosis) were more likely to have inadequate inpatient bowel preparation. Bowel preparation type did not affect the duration, quality of visualization, or successful cecal intubation.