A Randomized Controlled Trial to Assess the Safety and Efficacy of Carbon Dioxide Versus Air Insufflations in Colonoscopy

Background and purpose Recently, the endoscopic equipment have remarkablely improved and the technique of colonoscopic inserting were also progressive, in observation of the early detection of colorectal cancer and inflammatory bowel disease. However, some patients had the severe abdominal pain and fullness during and after colonoscopy. Recently, Saito et al reported to reduce those discomfort with using CO2 insufflation in Endoscopic submucosal dissection (ESD) of colorectal neoplasm in a prospective study. In this randomised controlled trial, we aim to investigate whether use of CO2 insufflation can reduce examinee discomfort in comparison with air insufflation during and after screening colonoscopy. Patients and Methods Patients were divided into two groups or. Patient (n = 205) receiving colonoscopy examinations were divided into 2 groups based on either the standard air insufflation or CO2 insufflation . Both insufflation procedures were also evaluated according to1) round of the abdomen before or after CS, 2) the time of insertion to the caecum, 3) Study measurements included a 100-mm visual analogue scale (VAS, 0 ~ 10; 0: painless, 10: unbearable pain) for patient pain during and after colonoscopy examinations (n = 81). 4) We investigated the comparison of VAS score between using CO2 insufflation and using air insufflation in identical patient who were previously preformed by CS with air insufflation. Result 1)Patient's abdominal discomfort significantly increased after CS in CO2 insufflation compared to the standard air insufflation . 2) The time for insertion was not significantly seen among the 2 groups (average ;13.89 min V.S 12.46min). 3) VAS scores of CO2 insufflation was significantly better than the standard air insufflation(average; 3.67 V.S 4.71). 4) Also, the degree of pain and fullness was reduced in CO2 insufflation compared to the standard air insufflation.Conclusions In the use of CO2 insufflations during and after screening colonoscopy , the time for insertion to caecum was not reduced, but abdominal pain and fullness were significantly reduced. So it was very useful for the colonoscopy. From now on, when it is expected there would be a long time CS, such as we perform CS strictly and beginners perform CS, the use of CO2 insufflations in Colorectal endoscopic examination is significantly useful.