Water infusion during colonoscopy reduces need for sedation and abdominal compression compared to air or CO2 insufflation

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Arquivos de gastroenterologia Published May 28, 2026 Medically reviewed May 30, 2026 Study authors: Rodriguez-Guzman Fernando, Arman Anna Carolina Orsini, Dias Marcelo Morganti Ferreira, Paternostro D… PubMed ↗ DOI ↗ By Dr. Julia Lee, PhD · Oncology, Genomics & Drug Development

Key Takeaway

Consider water infusion to reduce sedation and compression needs during colonoscopy without compromising cecal intubation.

This systematic review and meta-analysis examined the use of water infusion during colonoscopy compared to standard air or CO2 insufflation. The researchers pooled data from thirty randomized controlled trials involving patients undergoing this screening procedure. The primary focus was on adenoma detection rates, while secondary outcomes included cecal intubation success, time to reach the cecum, total procedure duration, and the need for abdominal compression or additional sedation.

The analysis revealed no significant difference in adenoma detection rates or the success rate of cecal intubation between the two methods. Additionally, the time required to reach the cecum and the total duration of the procedure did not differ significantly. These findings suggest that water infusion does not compromise the fundamental ability to visualize the colon or detect polyps compared to gas insufflation.

However, the study observed a significant reduction in the proportion of participants requiring on-demand sedation when water infusion was used. Similarly, the need for abdominal compression was significantly lower in the water infusion group. The authors highlight that water infusion facilitates easier navigation of the colonoscope to the cecum. No serious adverse events were reported, and tolerability was not a concern. The authors conclude that water infusion helps the colonoscope reach the cecum more easily, decreasing the need for on-demand sedation and abdominal compression.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedJan 2026

PMID42207083

View Original Abstract ↓

BACKGROUND: Colonoscopy is a widely used screening method for colorectal cancer, playing a crucial role in early detection and prevention by allowing visualization and removal of precancerous lesions. It also helps diagnose and manage neoplastic lesions and inflammatory bowel disease by providing direct visualization of the intestinal mucosa. However, traditional air or carbon dioxide (CO2) insufflation may limit complete visualization of the colon. Alternatively, water infusion causes local distension without elongating the colon (unlike air insufflation), while warm water reduces spasms, decreasing insertion time and patient discomfort. OBJECTIVE: This systematic review and meta-analysis aimed to compare water infusion versus air/CO2 insufflation in terms of technical efficacy, evaluate the effect of water immersion on procedural difficulty, and determine the accuracy of water immersion colonoscopy in detecting colon adenomas. METHODS: We searched MEDLINE, EMBASE, and Cochrane CENTRAL databases for randomized controlled trials published from inception to January 2023. Outcomes included adenoma detection rate, success rate of cecal intubation, cecal intubation time, total procedure time (from insertion to withdrawal), need for abdominal compression, and on-demand sedation rate. Thirty randomized controlled trials were included. RESULTS: adenoma detection rate, success rate of cecal intubation, cecal intubation time, and total procedure time showed no significant difference between the two methods (P>0.05). However, water infusion significantly reduced the proportion of participants requiring on-demand sedation (risk ratio 0.61, 95%CI 0.48-0.77, P=0.02) and abdominal compression (risk ratio 0.65, 95%CI 0.51-0.83, P<0.01). CONCLUSION: Colonoscopy with water infusion helps the colonoscope reach the cecum more easily, decreasing the need for on-demand sedation and abdominal compression.