How Good Is the Quality of Colonoscopy Preparation Under Monitored Anesthesia Care (Mac)?

Abstract

Purpose: MAC is used in our hospital endoscopy unit for colonoscopy in high risk patients (pts) only. However, routine instructions about overnight fasting in pts undergoing colonoscopy under MAC by the anesthesiologists limits the use of AM dose of split dose regimen, which may interfere with the quality of colon preparation (prep). The aim of our study was to compare the quality of colon prep in pts undergoing colonoscopy under MAC & conscious sedation (CS) at our hospital endoscopy unit by grading the endoscopic photographs. Methods: Patients: Between 01/07 and 04/08, 163 pts underwent colonoscopy under MAC (study group); 57 pts used polyethylene glycol (PEG) based solution, 66 pts used Phosphosoda + Dulcolax (P), and 40 used other solutions. Two hundred pts undergoing colonoscopies under CS using PEG (N = 100) & P (N = 100) served as controls. Assessment: Grading of Cleansing For Each Colonic Segment was done by a single observer looking at the colonoscopy photos- Poor prep = stool obscured the mucosa; Fair prep = 50–100% of mucosa visualized along with few specks of stool; Excellent prep = 100% of the mucosa visualized without any stool. The Colon Cleansing Score for each colonoscopy exam was based on the overall quality of prep in different segments of the colon. Score 3: Excellent prep in all the segments of colon; Score 2: Fair prep in at least 1 segment; Score 1: Poor prep in at least 1 segment. Results: A. Poor Prep Rate: Higher in pts having colonoscopy under MAC as compared to those undergoing in CS (26% vs. 13.5%, P < 0.05). B. Colon Cleansing Score: Worse in pts having procedure under MAC compared to those undergoing in CS (2.15 ± 0.07 vs. 2.38 ± 0.05, P < 0.05) C. Effect of Prep Solution on Colon Prep Rate: Worse with PEG solution in the MAC group compraed to CS group (36% vs. 16%, P < 0.05), but no difference with Phosphosoda + Dulcolax (18% vs 11%, P= NS). ASA score: In the MAC group, the mean ASA score was 2.42 ± 0.06 and the CS group was 2.01 ± 0.03. (P < 0.05) Conclusion: Poor colon preparation is frequent in patients undergoing colonoscopy under MAC and especially worse with the use of PEG solution. Since these patients are sicker (higher ASA class), a split dose may benefit them (these under current investigation).Figure