title: The water method for aiding colonoscope insertion: the learning curve of an experienced colonoscopist.
abstract: BACKGROUND: The water method has promising features for colonoscopy but the learning curve to master the technique is unknown.  AIMS: To describe the learning phase, and pitfalls of the water method and its impact on procedural outcomes by an experienced colonoscopist.  DESIGN: Review of prospectively collected data in a performance improvement project  SETTING: endoscopy Unit at a VA medical center  PATIENTS: 200 consecutive veterans undergoing colonoscopy  METHODS: An experienced colonoscopist examined 4 consecutive groups of 25 patients each using the water method to define the learning curve. Outcomes were compared to a historical cohort (n=100) examined by the same colonoscopist using usual air insufflation.  MAIN OUTCOME MEASURES: Intent-to-treat (ITT) cecal intubation rate.  RESULTS: ITT cecal intubation rate increased from 76% (first) to 96% (fourth quartile). Cecal intubation time in the first 2 quartiles was significantly longer (8.9±1.0 and 8.2±0.8 min, respectively) than that in the historical cohort (5.8±0.4 min) but decreased and became comparable to control values in the next 2 quartiles (7.2±0.9 and 6.6±0.6 min, respectively). Overall adenoma detection rate as a group (55%), compared favorably to the historical cohort (46%).  CONCLUSIONS: The water method is relatively easy to learn for an experienced colonoscopist. Mastery of the method resulted in cecal intubation rate and overall adenoma detection rate meeting quality performance standards.
authors.affiliation: Mayo Clinic Arizona, Scottsdale, AZ, USA.
authors.forename: Francisco C
authors.initials: FC
authors.lastname: Ramirez
authors.forename: Felix W
authors.initials: FW
authors.lastname: Leung