Role of Intravenous Hyoscine N-Butyl Bromide At the Time of Colonoscopic Withdrawal for Polyp Detection Rates: A Randomized, Double-Blinded, Placebo-Controlled Trial

Abstract

Background/Aims: Colonoscopy is currently the gold standard for detection and removal of colonic neoplasia. A number of factors may contribute to the accuracy of colonoscopy. Colonic spasm is a relatively common problem, and may impede colonoscopic insertion, inspection of the mucosal surface and polypectomy. Most endoscopists perform detection and removal of colonic polyps at the time of withdrawal, and they may often feel that colonic spasm makes detection and removal of colonic polyps difficult. The aim of this study was to determine whether there was any benefit for polyp detection rates in using hyoscine N-butyl bromide (Buscopan®) at the time of colonoscopic withdrawal. Methods: We conducted a randomized double-blinded, placebo controlled trial in a single center from July 2008 to September 2008. A total of 205 patients undergoing colonoscopy were randomized to receive either 20mg of hyoscine N-butyl bromide (Buscopan group (BG), n=103) or normal saline (placebo group (PG), n=102) intravenously at the time of colonoscopic withdrawal after cecal intubation. Outcome measures included polyp and adenoma detection rate, characteristics of polyps, insertion and withdrawal time, spasm score, vital signs, and side effects. Results: There was no difference of baseline characteristics between two groups. The polyp and adenoma detection rates in the BG were some higher than the PG, but there were no significant differences between two groups (respectively, 45.6% and 35.0% vs. 39.2% and 29.4%; p=0.353 and p=0.396). The size, location, number, shape and histology of polyps and adenomas did not significantly differ between two groups. No significant difference was found in the insertion time, withdrawal time and spasm score. Blood pressure after colonoscopy was significant lower than before colonoscopy in two groups, but pulse rate after colonoscopy was significant higher than before colonoscopy in BG (p=0.000). In side effects, dry mouth was significant higher in BG than PG (p=0.013). Conclusion: Intravenously administered hyoscine N-butyl bromide at the time of colonoscopic withdrawal cannot improve polyp and adenoma detection rates.