Water intubation method can reduce patients' pain and sedation rate in colonoscopy: a meta-analysis

Several randomized controlled trials (RCT) have shown that water infusion in lieu of air insufflation reduces sedation rate and pain score and increases cecal intubation rate in colonoscopy. The aim of the present study was to confirm the beneficial effects of the water intubation method over the air method. Electronic databases were searched to identify RCT reporting colonoscopy detection using the water method. The pooled data of sedation rate, pain score and other procedure-related outcomes were analyzed. Then, 15 full-text articles were selected and assessed. Nine trials with high-quality scores were enrolled into this meta-analysis including a total of 1414 participants. Pooled odds ratio (OR) of sedation rate was 0.392 (95% confidence interval (CI): 0.288-0.533, P = 0.000). Pooled weighted mean difference (WMD) of pain score was -1.543 (95% CI: -2.107--1.069,P = 0.000). Pooled OR of cecal intubation rate was 1.90 (95% CI: 1.29-2.82, P = 0.001). Pooled OR of polyp detection rate and adenoma detection rate were 0.805 (95% CI: 0.606-1.069, P = 0.134) and 0.913 (95% CI: 0.681-1.223, P = 0.168), respectively. Pooled WMD of cecal intubation time was 0.701 (95% CI: -0.486-1.889, P = 0.247). This meta-analysis confirmed that the water method significantly reduced sedation rate and degree of pain without decreasing cecal intubation rate and disease detection rate and without requiring more cecal intubation time, suggesting that the novel water method is better than the conventional air method in colonoscopy detection.