Water exchange (WE) and cap-assisted colonoscopy separately have been shown to reduce pain during insertion in unsedated patients. We hypothesized that compared with WE, WE cap-assisted colonoscopy (WECAC) could significantly lower real-time maximum insertion pain (RTMIP). Veterans without escort were recruited, randomized, blinded, and examined at 3 U.S. Veterans Affairs sites. The primary outcome was RTMIP, defined as the highest segmental pain (0 = no pain, 10 = most severe pain) during insertion. Randomization (WECAC, 143; WE, 137) produced an even distribution of a racially diverse group of men and women of low socioeconomic status. The intention-to-treat analysis reported results of WECAC and WE for cecal intubation (93% and 94.2%, respectively), mean RTMIP (2.9 [standard deviation {SD}, 2.5] and 2.6 [SD, 2.4]), proportion of patients with no pain (28.7% and 27.7%), mean insertion time (18.6 minutes [SD, 15.6] and 18.8 minutes [SD, 15.9]), and overall adenoma detection rate (48.3% and 55.1%); all values were >.05. When RTMIP was binarized as "no pain" (0) versus "some pain" (1-10) or "low pain" (0-7) versus "high pain" (8-10), different significant predictors of RTMIP were identified. Unsedated colonoscopy was appropriate for unescorted veterans. WE alone was sufficient. Adding a cap did not reduce RTMIP. Patient-specific factors and application of WE with insertion suction of infused water contributed to high and low RTMIP, respectively. For unescorted patients, selecting those with low anxiety, avoiding low body mass index, history of depression or self-reported poor health, and complying with the steps of WE can minimize RTMIP to ensure success of unsedated colonoscopy. (Clinical trial registration number: NCT03160859.)

中文翻译：

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在未镇静的退伍军人中进行水交换加帽与水交换结肠镜检查的前瞻性随机对照试验


水交换（WE）和帽辅助结肠镜检查分别已被证明可以减轻未镇静患者插入期间的疼痛。我们假设与 WE 相比，WE 帽辅助结肠镜检查 (WECAC) 可以显着降低实时最大插入疼痛 (RTMIP)。没有陪同的退伍军人在 3 个美国退伍军人事务中心被招募、随机、盲法和检查。主要结局是 RTMIP，定义为插入期间最严重的节段疼痛（0 = 无疼痛，10 = 最严重的疼痛）。随机化（WECAC，143；WE，137）产生了社会经济地位低下的种族多样化的男性和女性群体的均匀分布。意向治疗分析报告了盲肠插管的 WECAC 和 WE 结果（分别为 93% 和 94.2%）、平均 RTMIP（2.9 [标准差 {SD}, 2.5] 和 2.6 [SD, 2.4]）、无疼痛患者（28.7% 和 27.7%）、平均插入时间（18.6 分钟 [SD, 15.6] 和 18.8 分钟 [SD, 15.9]）以及总体腺瘤检出率（48.3% 和 55.1%）；所有值均为 >.05。当 RTMIP 被二值化为“无疼痛”(0) 与“有些疼痛”(1-10) 或“低度疼痛”(0-7) 与“高度疼痛”(8-10) 时，确定了 RTMIP 的不同显着预测因子。无镇静结肠镜检查适合无人陪同的退伍军人。仅靠我们就足够了。添加上限并不会降低 RTMIP。患者特定因素和 WE 与输注水插入抽吸的应用分别导致高和低 RTMIP。对于无人陪同的患者，选择焦虑程度低的患者，避免低体重指数、抑郁史或自述健康状况不佳的患者，并遵守WE的步骤，可以最大限度地减少RTMIP，以确保无镇静结肠镜检查的成功。 （临床试验注册号：NCT03160859。）