title: CO(2) insufflation for potentially difficult colonoscopies: efficacy when used by less experienced colonoscopists.
abstract: OBJECTIVE
  To clarify the effectiveness of CO(2) insufflation in potentially difficult colonoscopy cases, particularly in relation to the experience level of colonoscopists.
  
  
  METHODS
  One hundred twenty potentially difficult cases were included in this study, which involved females with a low body mass index and patients with earlier abdominal and/or pelvic open surgery or previously diagnosed left-side colon diverticulosis. Patients receiving colonoscopy examinations without sedation using a pediatric variable-stiffness colonoscope were divided into two groups based on either CO(2) or standard air insufflation. Both insufflation procedures were also evaluated according to the experience level of the respective colonoscopists who were divided into an experienced colonoscopist (EC) group and a less experienced colonoscopist (LEC) group. Study measurements included a 100-mm visual analogue scale (VAS) for patient pain during and after colonoscopy examinations, in addition to insertion to the cecum and withdrawal times.
  
  
  RESULTS
  Examination times did not differ, however, VAS scores in the CO(2) group were significantly better than in the air group (P < 0.001, two-way ANOVA) from immediately after the procedure and up to 2 h later. There were no significant differences between either insufflation method in the EC group (P = 0.29), however, VAS scores for CO(2) insufflation were significantly better than air insufflation in the LEC group (P = 0.023) immediately after colonoscopies and up to 4 h afterwards.
  
  
  CONCLUSIONS
  CO(2) insufflation reduced patient pain after colonoscopy in potentially difficult cases when performed by LECs.
authors.affiliation: Department of Endoscopy, Okayama University Hospital, Kita-ku, Okayama 700-8558, Japan. turaoka@md.okayama-u.ac.jp
authors.forename: Toshio
authors.initials: T
authors.lastname: Uraoka
authors.forename: Jun
authors.initials: J
authors.lastname: Kato
authors.forename: Motoaki
authors.initials: M
authors.lastname: Kuriyama
authors.forename: Keisuke
authors.initials: K
authors.lastname: Hori
authors.forename: Shin
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Keita
authors.initials: K
authors.lastname: Harada
authors.forename: Koji
authors.initials: K
authors.lastname: Takemoto
authors.forename: Sakiko
authors.initials: S
authors.lastname: Hiraoka
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Fujita
authors.forename: Joichiro
authors.initials: J
authors.lastname: Horii
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D015746:Abdominal Pain / Q000517:prevention & control; D000368:Aged; D002245:Carbon Dioxide / Q000627:therapeutic use*; D002983:Clinical Competence; D003113:Colonoscopy / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D007327:Insufflation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D002245:Carbon Dioxide