Carbon dioxide insufflation during endoscopic resection of large colorectal polyps can reduce post-procedure abdominal pain: A prospective, double-blind, randomized controlled trial

Background: Studies of the use of CO2 insufflation during endoscopic resection of large colorectal polyps (LCPs) are lacking. Objective: We evaluated the effect of CO2 insufflation on pain after endoscopic resection of LCPs. Methods: In a prospective randomized controlled trial (RCT), 132 patients were randomly assigned to groups who underwent endoscopic resection with CO2 insufflation (CO2 group, n = 66) or air insufflation (air group, n = 66). The primary outcome was abdominal pain post-procedure (PP). The secondary outcomes were abdominal distension, rates of technical success, amounts of sedatives prescribed, use of analgesics, and adverse events. Results: Baseline patient characteristics were similar between the groups. The mean abdominal pain score was 12.3 in the CO2 group vs. 17.5 in the air group at 1 h PP (p = 0.047). Also, the proportion of patients without pain was significantly higher in the CO2 group at 1 h PP (p= 0.008). The pain score differed more in the endoscopic submucosal dissection group and long-time group. The secondary outcomes were not significantly different between the two groups. Conclusions: The results of this RCT demonstrate the superiority of CO2 insufflation for endoscopic resection of LCPs in terms of decreasing PP abdominal pain (KCT0001636).