title: Water exchange enhanced cecal intubation in potentially difficult colonoscopy. Unsedated patients with prior abdominal or pelvic surgery: a prospective, randomized, controlled trial.
abstract: BACKGROUND
  Colonoscopy is widely used for management of colorectal diseases. A history of abdominal or pelvic surgery is a well-recognized factor associated with difficult colonoscopy. Although water exchange colonoscopy (WEC) was effective in small groups of male U.S. veterans with such a history, its application in other cultural settings is uncertain.
  
  
  OBJECTIVE
  To investigate the application of WEC in such patients.
  
  
  METHODS
  Prospective, randomized, controlled, patient-blinded study.
  
  
  METHODS
  Tertiary-care referral center in China.
  
  
  METHODS
  Outpatients with prior abdominal or pelvic surgery undergoing unsedated diagnostic, screening, or surveillance colonoscopy.
  
  
  METHODS
  Patients were randomized to examination by either WEC or conventional air colonoscopy (AC).
  
  
  METHODS
  Cecal intubation rate.
  
  
  RESULTS
  A total of 110 patients were randomized to the WEC (n = 55) or AC (n = 55) group. WEC significantly increased the cecal intubation rate (92.7% vs 76.4%; P = .033). The maximum pain scores (± standard deviation) were 2.1 ± 1.8 (WEC) and 4.6 ± 1.7 (AC), respectively (P < .001). Multivariate analysis showed that the colonoscopy method was the only independent predictor of failed colonoscopy (odds ratio 11.44, 95% confidence interval, 1.35-97.09). A higher proportion of patients examined by WEC would be willing to have a repeat unsedated colonoscopy (90.9% vs 72.7%, P = .013).
  
  
  CONCLUSIONS
  Single center; unblinded but experienced endoscopists.
  
  
  CONCLUSIONS
  This randomized, controlled trial confirms that the water exchange method significantly enhanced cecal intubation in potentially difficult colonoscopy in unsedated patients with prior abdominal or pelvic surgery. The lower pain scores and higher proportion accepting repeat of the unsedated option suggest that WEC is promising. It may enhances compliance with colonoscopy in specific populations. (
  
  
  BACKGROUND
  NCT01485133.).
authors: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, China.
authors: Hui
authors: H
authors: Luo
authors: Linhui
authors: L
authors: Zhang
authors: Xiaodong
authors: X
authors: Liu
authors: Felix W
authors: FW
authors: Leung
authors: Zhiguo
authors: Z
authors: Liu
authors: Xiangping
authors: X
authors: Wang
authors: Ling
authors: L
authors: Xue
authors: Kaichun
authors: K
authors: Wu
authors: Daiming
authors: D
authors: Fan
authors: Yanglin
authors: Y
authors: Pan
authors: Xuegang
authors: X
authors: Guo
mesh_terms: D000005:Abdomen / Q000601:surgery; D015746:Abdominal Pain / Q000209:etiology; D000328:Adult; D000368:Aged; D002432:Cecum; D002681:China; D003113:Colonoscopy / Q000009:adverse effects / Q000379:methods*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D007441:Intubation, Gastrointestinal; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D017060:Patient Satisfaction; D010388:Pelvis / Q000601:surgery; D016037:Single-Blind Method; D014867:Water
chemical_list: D006993:Hypnotics and Sedatives; D014867:Water