title: Randomized, double-blind trial of CO2 versus air insufflation in children undergoing colonoscopy.
abstract: OBJECTIVE
  Studies in adults have shown that postprocedural abdominal pain is reduced with the use of carbon dioxide (CO(2)) instead of air for insufflation during colonoscopy. The aim of our study was to compare postprocedural abdominal pain and girth in children undergoing colonoscopy using CO(2) or air for insufflation.
  
  
  METHODS
  This was a prospective, randomized, double-blind study that included 76 consecutive pediatric patients undergoing colonoscopy for various indications. Patients were randomly assigned to either CO(2) or air insufflation. At 2, 4, and 24 hours after the examination, the patients' pain was assessed by using the 11-point numerical rating scale. The waist circumference was measured 10 minutes and 2 and 4 hours after colonoscopy.
  
  
  RESULTS
  A significantly higher proportion of patients had no pain after colonoscopy in the CO(2) group compared with the air group (82 vs 37% at 2 hours and 95% vs. 63% at 4 hours, P < .001). Mean abdominal pain scores 2 and 4 hours after the procedure were statistically significantly lower in the CO(2) group compared with the control air group (0.5 vs 2.6 at 2 hours and 0.1 vs 1.2 at 4 hours, P < .001). There was no difference in waist circumference between the 2 groups at all time intervals.
  
  
  CONCLUSIONS
  The results of this randomized trial show clear benefits of CO(2) insufflation for colonoscopy in reducing postprocedural discomfort. (
  
  
  BACKGROUND
  NCT02407639.).
authors.affiliation: The Children's Hospital, University Medical Centre of Ljubljana, Ljubljana, Slovenia.
authors.forename: Matjaž
authors.initials: M
authors.lastname: Homan
authors.affiliation: The Children's Hospital, University Medical Centre of Ljubljana, Ljubljana, Slovenia.
authors.forename: Dora
authors.initials: D
authors.lastname: Mahkovic
authors.affiliation: The Children's Hospital, University Medical Centre of Ljubljana, Ljubljana, Slovenia.
authors.forename: Rok
authors.initials: R
authors.lastname: Orel
authors.affiliation: The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Petar
authors.initials: P
authors.lastname: Mamula
mesh_terms: D015746:Abdominal Pain / Q000209:etiology*; D000293:Adolescent; D000388:Air; D002245:Carbon Dioxide / Q000009:adverse effects*; D002648:Child; D003113:Colonoscopy / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007327:Insufflation / Q000009:adverse effects* / Q000379:methods*; D008297:Male; D010147:Pain Measurement; D011446:Prospective Studies; D055105:Waist Circumference
chemical_list: D002245:Carbon Dioxide