Comparison of Quality of Colonoscopy Bowel Preparation Among in-Patients, Out-Patients with Standard Bowel Preparation and Out-Patients Who Had Reinforcement of Instructions by Nurses

Abstract

Purpose: The aim of the study was to compare the quality of bowel preparation among in-patients, out-patients who underwent standard preparation and out-patients who had standard preparation along with reinforcement of instructions on bowel preparation by nurses prior to colonoscopy. Methods: Medical records and colonoscopy reports of patients who underwent a colonoscopy during April-May 2008, at a large tertiary care medical center, as in-patients (group-1) out-patients (group-2) and as out-patients in an affiliated satellite endoscopy center (group-3) were reviewed. Patients in all 3 Groups received standard bowel preparation whereas in group 3, patients additionally received nurse education on bowel preparation via a phone call one day prior to scheduled colonoscopy. Standard bowel preparation included either one gallon of PEG electrolyte solution (PEG-EL), oral Fleets-phospho soda (Fleets) or half a gallon of PEG-EL along with Bisacodyl (Halflytely). The quality of bowel preparation was graded by endoscopists according to a prespecified criteria, as excellent, good, fair or poor. The primary end point was selected as the percentage of patients with fair or poor bowel preparation, since visualization is compromized in these two categories. Results: There were a total of 136, 91 and 108 patients in the three groups respectively. Patient demographics such as age, gender and BMI were similar in all three groups. There were significantly higher number of patients who underwent screening colonoscopies in groups 2 and 3 and Fleets was more commonly used in these patients. In group 1, indication for colonoscopy was more likely to be GI bleeding, abdominal pain and diarrhea, and PEG-EL was the most commonly used agent. The primary end point (fair or poor preparation) was seen in 50% in group 1, 36% in group 2 and 13% in group 3 (P < 0.001). Colonoscopy completion rates were 73%, 84% and 97% respectively (P < 0.001). On multivariable logistic regression analysis, out-patients who received nurse education on bowel preparation were 68% less likely to have a poor/fair preparation compared with out-patients with standard preparation, while there was no statistically significant difference between in-patients and out-patients with standard preparation (see Table).Table: Fair/Poor Colonoscopy Preparation: Multivariable logistic regression analysis.Conclusion: Reinforcement of instructions on bowel preparation by nurses via phone call one day prior to colonoscopy significantly improves quality of bowel preparation among out-patients. Similar interventions should be considered by other centers to improve quality of colonoscopy. While in-patients had significantly higher rates of poor/ fair bowel preparation by uni-variate analysis compared to out-patients, there was no significant difference when adjusted for other confounders.