Warm water infusion colonoscopy: a review and meta-analysis

Background and study aims: Warm water infusion instead of traditional air insufflation during the insertion phase of colonoscopy has been proposed to reduce pain and improve patient acceptance of the procedure. This systematic review aimed to compare warm water infusion with standard air insufflation according to findings from randomized controlled trials (RCTs).

Methods: In a systematic review and meta-analysis of RCTs comparing warm water infusion with standard air insufflation, primary outcome measures were procedure-related (cecal intubation, time to cecal intubation, and adenoma detection rates) and patient-related (pain).

Results: Nine studies (1283 patients) were included. Warm water infusion, as sole modality for facilitating insertion, was associated with a fourfold higher risk of cecal intubation failure compared with air insufflation (risk ratio [RR] 4.01, confidence interval [CI] 1.17 to 13.78, P = 0.03), but this risk did not significantly differ between warm water infusion and air insufflation with the hybrid technique (i. e., brief use of air when difficulty, e. g. poor view, was encountered). Warm water infusion and air insufflation were associated with similar cecal intubation times (P = 0.62) and adenoma detection rates (P = 0.49), but with warm water infusion patients experienced significantly less pain (P < 0.00001) and a significantly lower proportion requested sedation and/or analgesia (RR 0.48, CI 0.35 to 0.66, P < 0.00001).

Conclusions: Although failure of cecal intubation is more frequent with warm water infusion, technical modifications, i. e., short air insufflations, can abolish this. Warm water infusion is less painful than standard air insufflation, reduces the need for sedation/analgesia, and improves patient acceptance of colonoscopy, without additional adverse reactions.

• References

• 1 Preventive Services Task Force. Screening for colorectal cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2008; 149: 627-637
• 2 Winawer SJ, Zauber AG, Ho MN et al. Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med 1993; 329: 1977-1981
• 3 Brenner H, Hoffmeister M, Arndt V et al. Protection from right- and left-sided colorectal neoplasms after colonoscopy: population-based study. J Natl Cancer Inst 2010; 102: 89-95
• 4 Landsdorp-Vogelaar I, Knudsen AB, Brenner H. Cost–effectiveness of colorectal cancer screening – an overview. Best Pract Res Clin Gastroenterol 2010; 24: 439­449
• 5 Davila RE, Rajan E, Baron TH et al. ASGE guideline: colorectal cancer screening and surveillance. Gastrointest Endosc 2006; 63: 546-557
• 6 Robertson RH, Burkhardt JH, Powell MP et al. Trends in colon cancer screening procedures in the US Medicare and Tricare populations: 1999–2001. Prev Med 2006; 42: 460-462
• 7 Whitlock EP, Lin JS, Liles E et al. Screening for colorectal cancer: a targeted, updated systematic review for the U.S. Preventive Services Task Force.. Ann Intern Med 2008; 149: 638-658
• 8 Harris JK, Vader JP, Wietlisbach V et al. Variations in colonoscopy practice in Europe: a multicentre descriptive study (EPAGE). Scand J Gastroenterol 2007; 42: 126-134
• 9 Seip B, Bretthauer M, Dahler S et al. Patient satisfaction with on-demand sedation for outpatient colonoscopy. Endoscopy 2010; 42: 639-646
• 10 Froehlich F, Harris JK, Wietlisbach V et al. Current sedation and monitoring practice for colonoscopy: an international observational study (EPAGE). Endoscopy 2006; 38: 461-469
• 11 Ladas SD, Satake Y, Mostafa I et al. Sedation practices for gastrointestinal endoscopy in Europe, North America, Asia, Africa and Australia. Digestion 2010; 82: 74-76
• 12 Rex DK, Imperiale TF, Portish V. Patients willing to try colonoscopy without sedation: associated clinical factors and results of a randomized controlled trial. Gastrointest Endosc 1999; 49: 554-559
• 13 Petrini JL, Egan JV, Hahn WV. Unsedated colonoscopy: patient characteristics and satisfaction in a community-based endoscopy unit. Gastrointest Endosc 2009; 69: 567-572
• 14 Leung FW. Methods of reducing discomfort during colonoscopy. Dig Dis Sci 2008; 53: 1462-1467
• 15 Leung FW. Water-related techniques for performance of colonoscopy. Dig Dis Sci 2008; 53: 2847-2850
• 16 Leung FW, Leung JW, Mann SK et al. DDW 2011 cutting edge colonoscopy techniques – state of the art lecture master class – warm water infusion/CO₂ insufflation for colonoscopy. J Interv Gastroenterol 2011; 1: 78-82
• 17 Falchuk ZM, Griffin PH. A technique to facilitate colonoscopy in areas of severe diverticular disease. N Engl J Med 1984; 310: 598
• 18 Baumann UA. Water intubation of the sigmoid colon: water instillation speeds up left-sided colonoscopy. Endoscopy 1999; 31: 314-317
• 19 Church JM. Warm water irrigation for dealing with spasm during colonoscopy: simple, inexpensive, and effective. Gastrointest Endosc 2002; 56: 672-674
• 20 Egger M, Davey SmithG, Schneider M et al. Bias in meta-analysis detected by a simple, graphical test. BMJ 1997; 315: 629-634
• 21 Higgins JPT, Green S editors Cochrane handbook for systematic reviews of interventions version 5.1.0 [updated March 2011]. The Cochrane Collaboration; 2011 Available from: www.cochrane-handbook.org
• 22 Schünemann HJ, Oxman AD, Brozek J et al. GRADE: assessing the quality of evidence for diagnostic recommendations. Evid Based Med 2008; 13: 162-163
• 23 Leung CW, Kaltenbach T, Soetikno R et al. Water immersion versus standard colonoscopy insertion technique: randomized trial shows promise for minimal sedation. Endoscopy 2010; 42: 557-563
• 24 Leung FW, Harker JO, Jackson G et al. A proof-of-principle, prospective, randomized, controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method. Gastrointest Endosc 2010; 72: 693-700
• 25 Leung JW, Mann SK, Siao-Salera R 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; 70: 505-510
• 26 Leung J, Mann S, Siao-Salera R 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; 73: 103-110
• 27 Ransibrahmanakul K, Leung JW, Mann SK et al. Comparative effectiveness of water vs. air methods in minimal sedation colonoscopy performed by supervised trainees in the US – randomized controlled trial. Am J Clin Med 2010; 7: 113-118
• 28 Amato A, Radaelli F, Paggi S et al. Carbon dioxide insufflation and warm water infusion versus standard air insufflation: Preliminary results of a randomized controlled trial in unsedated colonoscopy. Gastrointest Endosc 2011; 73: 137
• 29 Radaelli F, Paggi S, Amato A et al. Warm water infusion versus air insufflation for unsedated colonoscopy: a randomized, controlled trial. Gastrointest Endosc 2010; 72: 701-709
• 30 Pohl J, Messer I, Behrens A et al. Water infusion for cecal intubation increases patient tolerance, but does not improve intubation of unsedated colonoscopies. Clin Gastroenterol Hepatol 2011; 9: 1039-1043 Epub 2011 Jul 13
• 31 Hsieh YH, Lin HJ, Tseng KC. Limited water infusion decreases pain during minimally sedated colonoscopy. World J Gastroenterol 2011; 17: 2236-2240
• 32 Francis DL, Rodriguez-Correa DT, Buchner A et al. Application of a conversion factor to estimate the adenoma detection rate from the polyp detection rate. Gastrointest Endosc 2011; 73: 493-497
• 33 Leung FW. Water exchange may be superior to water immersion for colonoscopy. Clin Gastroenterol Hepatol 2011; 9: 1012-1014
• 34 Kim WH, Cho YJ, Park JY et al. Factors affecting insertion time and patient discomfort during colonoscopy. Gastrointest Endosc 2000; 52: 600-605
• 35 Day LW, Kwon A, Inadomi JM et al. Adverse events in older patients undergoing colonoscopy: a systematic review and meta-analysis. Gastrointest Endosc 2011; 74: 885-896