A proof-of-principle, prospective, randomized, controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method.
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).
Leung
Felix W
FW
Research and Medical Services, Sepulveda Ambulatory Care Center, Veterans Affairs Greater Los Angeles Healthcare System, North Hills, California, USA. felix.leung@va.gov
Harker
Judith O
JO
Jackson
Guy
G
Okamoto
Kate E
KE
Behbahani
Omid M
OM
Jamgotchian
Nora J
NJ
Aharonian
H Steven
HS
Guth
Paul H
PH
Mann
Surinder K
SK
Leung
Joseph W
JW
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
D014867:Water