Department of Medicine, Evergreen General Hospital, Taoyuan.
Division of Gastroenterology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi.
J Clin Gastroenterol. 2021;55(10):869-875. doi: 10.1097/MCG.0000000000001454.
To test the hypothesis that water exchange (WE), when compared with carbon dioxide (CO2) insufflation, significantly reduces the right colon adenoma miss rate (rAMR) in a blinded randomized controlled trial with cap-assisted colonoscopy.
The unblinded consecutive group observational data showed that WE significantly decreased rAMR. The unblinded data are limited by potential bias.
Consecutive patients aged 45 years or more were randomized to undergo insertion with WE or CO2. Withdrawal and polypectomy were performed with CO2 in both groups to the hepatic flexure. The colonoscope was reinserted to the cecum. A second colonoscopist re-examined the right colon. The second colonoscopist was unaware, but made a guess, of the initial insertion method. The number of additional adenomas divided by the total number detected in both examinations equaled rAMR.
Among 262 patients (131/group), demographic variables were similar. The body mass index was significantly higher in the WE group. Compared with CO2, WE significantly decreased rAMR [18.0% (33/183) vs. 34.6% (62/179), P=0.0025] and right colon serrated polyp miss rate [17.4% (27/155) vs. 39.3% (33/84), P=0.002]. Multivariate logistic regression analysis showed that WE was an independent predictor of rAMR (odds ratio, 0.42; 95% confidence interval, 0.21-0.86), and so was ≥2 adenomas in the right colon (odds ratio, 2.35; 95% confidence interval, 1.17-4.76). Whether the second colonoscopist guessed the insertion method correctly or not, and demographic and procedure variables were not associated with rAMR.
The randomized controlled trial validated unblinded observational data showing that WE significantly decreased rAMR and right colon serrated polyp miss rate (clinical trial registration number: NCT03845933).
通过一项盲法随机对照试验，检验与二氧化碳（CO2）充气相比，水交换（WE）是否能显著降低盲法随机对照试验中右结肠腺瘤漏诊率（rAMR）的假说。
非盲连续组观察数据显示 WE 显著降低了 rAMR。非盲数据受到潜在偏倚的限制。
连续纳入年龄 45 岁及以上的患者，随机分为 WE 组或 CO2 组行插入操作。两组患者均在 CO2 充气下退镜至肝曲，然后重新插入结肠镜至盲肠。由第二位结肠镜医师对右半结肠进行再次检查。第二位结肠镜医师对初次插入方法不知情，但进行猜测。将两次检查中发现的额外腺瘤数除以两次检查发现的总腺瘤数，即得到 rAMR。
262 例患者（每组 131 例）中，两组患者的人口统计学变量相似。WE 组的体重指数显著更高。与 CO2 相比，WE 显著降低了 rAMR[18.0%（33/183）比 34.6%（62/179），P=0.0025]和右半结肠锯齿状息肉漏诊率[17.4%（27/155）比 39.3%（33/84），P=0.002]。多变量逻辑回归分析显示，WE 是 rAMR 的独立预测因素（优势比，0.42；95%置信区间，0.21-0.86），右半结肠有≥2 个腺瘤也是 rAMR 的独立预测因素（优势比，2.35；95%置信区间，1.17-4.76）。无论第二位结肠镜医师是否猜对插入方法，以及人口统计学和手术变量均与 rAMR 无关。
该随机对照试验验证了非盲观察性数据，表明 WE 显著降低了 rAMR 和右半结肠锯齿状息肉漏诊率（临床试验注册号：NCT03845933）。
