Review articleWater-aided colonoscopy: a systematic review
Section snippets
Methods
Because the last review1 covered the literature through 2007, Medline, PubMed, and Google (January 2008-December 2011), searches were considered to identify appropriate RCTs (published or in press). In 9 RCTs, the pain scale of 0 = no pain and 10 = most severe or worst pain was used. In 2, a scale of 0 = no pain and 100 = most severe or worst pain was used,7, 11 and in 1, the scale of 0 = no pain and 5 = most severe or worst pain was used.8 The pain scores in the latter 3 RCTs were recomputed
Results
Our review identified 12 RCTs that compared air insufflation with water-aided methods. Access to the full report for writing an editorial comment17 provided the needed information in 1 report.
Table 1 shows the demographic and procedure-related variables. In each of these studies, the randomization appeared to have distributed equivalent patients to each of the air and water groups evenly. The mean (SD) or median (IQR) pain score in the air insufflation and water-aided method groups are shown in
Discussion
The emerging interest in water-aided methods for colonoscopy is suggested by recent RCTs,2, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 observational studies,4, 5, 18, 19 retrospective reports,6, 10, 20, 21, 22, 23, 24, 25 commentaries,26, 27, 28, 29, 30, 31, 32, 33, 34 hypothesis papers,35 editorials,35, 36, 37, 38 and reviews.39, 40, 41, 42, 43 Water immersion entails distention of the colon by infused water, which is removed predominantly during withdrawal. On the other hand, the explicit goal
References (77)
- et al.
A new water instillation method for colonoscopy without sedation as performed by endoscopists-in-training
Gastrointest Endosc
(2002) - et al.
Impact of a novel water method on scheduled unsedated colonoscopy in U.S. veterans
Gastrointest Endosc
(2009) - et al.
Warm water infusion versus air insufflation for unsedated colonoscopy: a randomized, controlled trial
Gastrointest Endosc
(2010) - et al.
A randomized controlled comparison of warm water infusion in lieu of air insufflation versus air insufflation for aiding colonoscopy insertion in sedated patients undergoing colorectal cancer screening and surveillance
Gastrointest Endosc
(2009) - et al.
A proof-of-principle, prospective, randomized controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method
Gastrointest Endosc
(2010) - et al.
A randomized, controlled trial to confirm the beneficial effects of the water method on U.S. veterans undergoing colonoscopy with the option of on-demand sedation
Gastrointest Endosc
(2011) - et al.
Water-immersion sigmoidoscopy to treat acute GI bleeding in the perioperative period after surgical colorectal anastomosis
Gastrointest Endosc
(2010) - et al.
Water-assisted unsedated colonoscopy: Does the end justify the means?
Gastrointest Endosc
(2009) - et al.
The demise of air insufflation and the rise of the warm water infusion method
Gastrointest Endosc
(2009) Unsedated colonoscopy: Just add water?
Gastrointest Endosc
(2010)
Involvement of trainees in routine unsedated colonoscopy—review of pilot experience
Gastrointest Endosc
Colonoscopic miss rates for right-sided colon cancer: a population-based analysis
Gastroenterology
Impact of wide-angle, high-definition endoscopy in the diagnosis of colorectal neoplasia: a randomized controlled trial
Gastroenterology
Effect of institution-wide policy of colonoscopy withdrawal time ≥7 minutes on polyp detection
Gastroenterology
The impact of narrow band imaging in screening colonoscopy: a randomized controlled trial
Clin Gastroenterol Hepatol
The effect of periodic monitoring and feedback on screening colonoscopy withdrawal times, polyp detection rates, and patient satisfaction scores
Gastrointest Endosc
Impact of experience with a retrograde-viewing device on adenoma detection rates and withdrawal times during colonoscopy: the Third Eye Retroscope Study Group
Gastrointest Endosc
A retrograde-viewing device improves detection of adenomas in the colon: a prospective efficacy evaluation (with videos)
Gastrointest Endosc
Effect of a retrograde-viewing device on adenoma detection rate during colonoscopy: the “TERRACE” Study
Gastrointest Endosc
The impact of suboptimal bowel preparation on adenoma miss rates and the factors associated with early repeat colonoscopy
Gastrointest Endosc
An endoscopist-blinded, randomized, controlled trial of a simple visual aid to improve bowel preparation for screening colonoscopy
Gastrointest Endosc
A randomized clinical study comparing reduced-volume oral sulfate solution with standard 4-liter sulfate-free electrolyte lavage solution as preparation for colonoscopy
Gastrointest Endosc
Water exchange may be superior to water immersion for colonoscopy (editorial)
Clin Gastroenterol Hepatol
Water-related method for performance of colonoscopy
Dig Dis Sci
Colonoscopy insertion technique using water immersion versus standard technique: a randomized trial showing promise for minimal-sedation colonoscopy
Endoscopy
Option for screening colonoscopy without sedation—a pilot study in United States veterans
Aliment Pharmacol Ther
Retrospective data showing the water method increased adenoma detection rate—a hypothesis generating observation
J Interv Gastroenterol
Warm water or oil-assisted colonoscopy: toward simpler examinations?
Am J Gastroenterol
Usefulness of warm water and oil assistance in colonoscopy by trainees
Dig Dis Sci
Limited water infusion decreases pain during minimally sedated colonoscopy
World J Gastroenterol
Feasibility of colonoscopy with water infusion in minimally sedated patients in an Asian community setting
J Interv Gastroenterol
Comparative effectiveness of water vs. air methods in minimal sedation colonoscopy performed by supervised trainees in the US—a RCT
Am J Clin Med
A head-to-head comparison of the water vs. air method in patients undergoing screening colonoscopy
J Interv Gastro
Water infusion for cecal intubation increases patient tolerance, but does not improve intubation of unsedated colonoscopies
Clin Gastroenterol Hepatol
The water method is effective in difficult colonoscopy—it enhances cecal intubation in unsedated patients with a history of abdominal surgery
J Interv Gastroenterol
The water method combined with chromoendoscopy enhances adenoma detection
J Interv Gastroenterol
Adopting the water method: lessons, tips and pitfalls learned
Am J Clin Med
The water method for aiding colonoscope insertion: the learning curve of an experienced colonoscopist
J Interv Gastroenterol
Cited by (95)
Interventions to improve adenoma detection rates for colonoscopy
2022, Gastrointestinal EndoscopyColonoscopic techniques in polyp detection: An Egyptian study
2021, Revista de Gastroenterologia de MexicoColonoscopy, Polypectomy, and Related Techniques
2020, Pediatric Gastrointestinal and Liver Disease, Sixth EditionImpact of linked-color imaging on colorectal adenoma detection
2019, Gastrointestinal EndoscopyASGE review of adverse events in colonoscopy
2019, Gastrointestinal Endoscopy
DISCLOSURE: The study was supported in part by Veterans Affairs Medical Research Funds at Veterans Affairs Greater Los Angeles Healthcare System and an American College of Gastroenterology Clinical Research Award (F.W.L). No other financial relationships relevant to this publication were disclosed.