title: A proof-of-principle, prospective, randomized, controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method.
abstract: BACKGROUND
  An observational study in veterans showed that a novel water method (water infusion in lieu of air insufflation) enhanced cecal intubation and willingness to undergo a repeat scheduled unsedated colonoscopy.
  
  
  OBJECTIVE
  To confirm these beneficial effects and significant attenuation of discomfort in a randomized, controlled trial (RCT).
  
  
  METHODS
  Prospective RCT, intent-to-treat analysis.
  
  
  METHODS
  Veterans Affairs ambulatory care facility.
  
  
  METHODS
  Veterans undergoing scheduled unsedated colonoscopy.
  
  
  METHODS
  During insertion, the water and traditional air methods were compared.
  
  
  METHODS
  Discomfort and procedure-related outcomes.
  
  
  RESULTS
  Eighty-two veterans were randomized to the air (n = 40) or water (n = 42) method. Cecal intubation (78% vs 98%) and willingness to repeat (78% vs 93%) were significantly better with the water method (P < .05; Fisher exact test). The mean (standard deviation) of maximum discomfort (0 = none, 10 = most severe) during colonoscopy was 5.5 (3.0) versus 3.6 (2.1) P = .002 (Student t test), and the median overall discomfort after colonoscopy was 3 versus 2, P = .052 (Mann-Whitney U test), respectively. The method, but not patient characteristics, was a predictor of discomfort (t = -1.998, P = .049, R(2) = 0.074). The odds ratio for failed cecal intubation was 2.09 (95% CI, 1.49-2.93) for the air group. Fair/poor previous experience increased the risk of failed cecal intubation in the air group only. The water method numerically increased adenoma yield.
  
  
  CONCLUSIONS
  Single site, small number of elderly men, unblinded examiner, possibility of unblinded subjects, restricted generalizability.
  
  
  CONCLUSIONS
  The RCT data confirmed that the water method significantly enhanced cecal intubation and willingness to undergo a repeat colonoscopy. The decrease in maximum discomfort was significant; the decrease in overall discomfort approached significance. The method, but not patient characteristics, was a predictor of discomfort. (Clinical trial registration number NCT00747084).
authors.affiliation: Research and Medical Services, Sepulveda Ambulatory Care Center, Veterans Affairs Greater Los Angeles Healthcare System, North Hills, California, USA. felix.leung@va.gov
authors.forename: Felix W
authors.initials: FW
authors.lastname: Leung
authors.forename: Judith O
authors.initials: JO
authors.lastname: Harker
authors.forename: Guy
authors.initials: G
authors.lastname: Jackson
authors.forename: Kate E
authors.initials: KE
authors.lastname: Okamoto
authors.forename: Omid M
authors.initials: OM
authors.lastname: Behbahani
authors.forename: Nora J
authors.initials: NJ
authors.lastname: Jamgotchian
authors.forename: H Steven
authors.initials: HS
authors.lastname: Aharonian
authors.forename: Paul H
authors.initials: PH
authors.lastname: Guth
authors.forename: Surinder K
authors.initials: SK
authors.lastname: Mann
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Leung
mesh_terms: D000236:Adenoma / Q000175:diagnosis; D000368:Aged; D000388:Air; D002432:Cecum; D003110:Colonic Neoplasms / Q000175:diagnosis; D003113:Colonoscopy / Q000009:adverse effects / Q000379:methods*; D016292:Procedural Sedation; D006801:Humans; D007327:Insufflation / Q000379:methods*; D057194:Intention to Treat Analysis; D007441:Intubation, Gastrointestinal; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011446:Prospective Studies; D014481:United States; D014728:Veterans; D014867:Water / Q000008:administration & dosage
chemical_list: D014867:Water