P2492 - The Evolving Practice of Water-Aided Colonoscopy (WAC) – An International Survey of Colonoscopists

Felix Leung, MD¹, Sergio Cadoni, MD², Andrew Yen, MD³, Piet de Groen, MD⁴, Keith Siau, MBChB⁵, Yu-Hsi Hsieh, MD⁶, Sauid Ishaq, MD⁷, Chi-Liang Cheng, MD⁸, Francisco C. Ramirez, MD, FACG⁹, Adrian Bak, MD¹⁰, William Karnes, MD¹¹, Putut Bayupurnama, MD¹², Joseph Leung, MD^3
1Sepulveda Ambulatory Care Center, VAGLAHS, North Hills, CA; ²St. Barbara Hospital, Iglesias (CI), Sardegna, Italy; ³Sacramento VAMC, Veterans Affairs Northern California Healthcare System, Mather, CA; ⁴University of Minnesota, Minneapolis, MN; ⁵The Dudley Group NHS Foundation Trust, Dudley, England, United Kingdom; ⁶Dalin Tzu Chi Hospital, Tzu Chi Medical Foundation, Chiayi, Chiayi, Taiwan; ⁷The Dudley Group of Hospitals NHS Trust, Birmingham, England, United Kingdom; ⁸Evergreen General Hospital, Taoyuan, Taipei, Taiwan; ⁹Mayo Clinic, Scottsdale, AZ; ¹⁰University of British Columbia, Kelowna General Hospital, Kelowna, BC, Canada; ¹¹Digestive Health Institute, University of California Irvine Medical Center, Irvine, CA; ¹²Universitas Gadjah Mada, Dr. Sardjito General Hospital, Kabupaten Sleman, Yogyakarta, Indonesia

Introduction: A water-aided technique (water immersion, WI) as an adjunct to gas insufflation was described in 1984. Water was infused to aid insertion through colonic segments deformed by diverticulosis, and the infused water was removed during withdrawal. Water exchange (WE) was described in 2010. Water infusion without air was used to aid insertion, followed by almost simultaneous removal of the infused water to minimize distention and to provide salvage cleaning. Worldwide, >80 reports on water-aided colonoscopy (WAC) have been published by 2020, documenting a steady growth in WE usage. A modified Delphi consensus review on WAC (GIE 2021;93:1411) reported that WE produces less pain and higher adenoma detection rates (ADR) than WI; underwater resection (UWR) is feasible, and has been applied to routine and salvage polypectomy.

Methods: IWATERS (International Water-Aided Technique for Endoscopy and Research Society) conducted a survey to assess the clinical practice of WAC. Factors that might affect uptake of WAC were explored: colonoscopist demographics and experience, practice settings, allocated procedure time, the learning medium, perceived ease of learning and learning preference. A survey link was e-mailed to 55 co-authors of the Delphi review and distributed to their colleagues and trainees.

Results: One hundred responses were received (from 84 practicing clinicians, 16 trainees). Responses with >80% affirmative answers (Table 1a) included: use of WAC, unlearning old methods to learn WAC is easier than expected, learning WAC is easy, clinical practice is in constant flux, WAC provides gains for my practice, have time to implement WAC, promote WAC in my practice, positive outcomes WAC vs. gas (air or CO₂), and no reservations using WAC. Learning WAC was predominantly through coaching by mentors or colleagues and in a lesser degree from reading, viewing videos or attending seminars. Table 1b shows that more use of WI in respondents with usual scheduled colonoscopy time ≤30 minutes (p=0.026); and more use of WE (p=0.043) in respondents with usual scheduled colonoscopy time >30 minutes

Discussion: After learning the methods from mentors or colleagues, the surveyed endoscopists implement WAC (WI or WE) in their practice for the perceived positive benefits WAC provides their patients, even at the expense of increased procedure time (10 min) for WE. Coaching appeared to be the most popular method to acquire WAC skills. Usual scheduled colonoscopy time >30 min favors the use of WE.



Disclosures:


Felix Leung, MD¹, Sergio Cadoni, MD², Andrew Yen, MD³, Piet de Groen, MD⁴, Keith Siau, MBChB⁵, Yu-Hsi Hsieh, MD⁶, Sauid Ishaq, MD⁷, Chi-Liang Cheng, MD⁸, Francisco C. Ramirez, MD, FACG⁹, Adrian Bak, MD¹⁰, William Karnes, MD¹¹, Putut Bayupurnama, MD¹², Joseph Leung, MD³. P2492 - The Evolving Practice of Water-Aided Colonoscopy (WAC) – An International Survey of Colonoscopists, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.