title: Carbon dioxide insufflation during endoscopic retrograde cholangiopancreatography: a review and meta-analysis.
abstract: OBJECTIVE
  The role of carbon dioxide (CO2) insufflation during endoscopic retrograde cholangiopancreatography (ERCP) is debated. A meta-analysis was performed to evaluate the efficacy and safety of CO2 insufflation for ERCP.
  
  
  METHODS
  Searches were conducted in multiple databases composed of Pub-Medline, EMBASE, the Cochrane Library, science citation index expanded, Google scholar, and CNKI China series full-text database. Outcome measurements are listed below: ERCP procedural data, post-ERCP abdominal discomfort, radiographic evaluation of bowel gas volume, and CO2 safety data concerning CO2 elimination.
  
  
  RESULTS
  Seven published randomized clinical trials involving 756 patients fulfilling the inclusion criteria were selected for meta-analysis, almost all of high quality. The incidence of ERCP-related complications was reduced by CO2 insufflation, so were the events of 1-hour, 3-hour, and 6-hour post-ERCP abdominal pain, based on their corresponding statistical results. Besides, CO2 insufflation was associated with less gas volume in the bowel lumen after the procedure. There were no significant differences between CO2 and air insufflation in total procedure time, the success rate of selective cannulation, post-ERCP abdominal distension, respectively. Subsequent sensitivity and subgroup analyses produced conflicting results.
  
  
  CONCLUSIONS
  Compared with air insufflation, CO2 insufflation during ERCP reduces post-ERCP abdominal pain, post-ERCP bowel remnant gas volume, and ERCP-related complications, without clinically significant systematic CO2 retention.
authors.affiliation: From the *Department of Gastrointestinal Endoscopy, Fujian Provincial Tumor Hospital, Teaching Hospital of Fujian Medical University, Fuzhou, Fujian, China; †Institute of Minimally Invasive Medicine, Tongji University, Shanghai, China; and ‡Department of Surgery, Fujian Provincial Tumor Hospital, Teaching Hospital of Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.forename: Suyu
authors.initials: S
authors.lastname: Chen
authors.forename: Gyanendra
authors.initials: G
authors.lastname: Swar
authors.forename: YongGuang
authors.initials: Y
authors.lastname: Wang
authors.forename: MinGang
authors.initials: M
authors.lastname: Ying
mesh_terms: D015746:Abdominal Pain / Q000209:etiology / Q000517:prevention & control; D000388:Air; D002245:Carbon Dioxide; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects* / Q000379:methods*; D004064:Digestive System / Q000000981:diagnostic imaging; D006801:Humans; D007327:Insufflation / Q000009:adverse effects* / Q000379:methods*; D016032:Randomized Controlled Trials as Topic; D012449:Safety
chemical_list: D002245:Carbon Dioxide