title: [Safety and efficacy of carbon dioxide insufflation during colonoscopy].
abstract: OBJECTIVE
  To assess the safety and efficacy of carbon dioxide (CO(2)) in colonoscopy examination.
  
  
  METHODS
  We randomized 349 patients to undergo colonoscopy with insufflation of air (n=175) or CO(2) (n=174). At colonoscopy, p (ET CO(2)) was observed at 4 time points: before the exam, arrived caecum, back rectum, and after the exam. Patient's experience of pain in the end and after the examination at 1, 3, 6, and 24 h was registered using a visual analog scale (VAS). Sedation was not used routinely.
  
  
  RESULTS
  The groups were similar in age, sex, inspection time, and caecal intubation rate (all P>0.05). There were no significant differences in p (ET CO(2)) values between the 2 groups before and after the procedure (all P>0.05). VAS scores in the CO(2) group at various time points after the examination were significantly lower than those in the air group (all P<0.05). The percent of VAS scores of 0 in the CO(2) group after 1, 3, 6, and 24 h was significantly higher than that in the air group (all P<0.01).
  
  
  CONCLUSIONS
  Injection of CO(2) for colonoscopy will not cause CO(2) retention, and it may significantly reduce the pain, which is safe and effective.
authors.affiliation: Department of Gastroenterology, Second Xiangya Hospital, Central South University, Changsha 410011, China.
authors.forename: Xiongxiang
authors.initials: X
authors.lastname: Liu
authors.forename: Deliang
authors.initials: D
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Dalian
authors.initials: D
authors.lastname: Ou
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Zhou
mesh_terms: D015746:Abdominal Pain / Q000517:prevention & control*; D000328:Adult; D001785:Blood Gas Monitoring, Transcutaneous; D002245:Carbon Dioxide; D003113:Colonoscopy / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012449:Safety
chemical_list: D002245:Carbon Dioxide