To evaluate if out-of-hospital administration of fentanyl and intranasal ketamine, compared to fentanyl alone, improves early pain control after injury. We conducted an out-of-hospital randomized, placebo-controlled, blinded, parallel group clinical trial from October 2017 to December 2021. Participants were male, aged 18 to 65 years, receiving fentanyl to treat acute traumatic pain prior to hospital arrival, treated by an urban fire-based emergency medical services agency, and transported to the region’s only adult Level I trauma center. Participants randomly received 50 mg intranasal ketamine or placebo. The primary outcome was the proportion with a minimum 2-point reduction in self-described pain on the verbal numerical rating scale 30 minutes after study drug administration assessed by 95% confidence interval overlap. Secondary outcomes were side effects, pain ratings, and additional pain medications through the first 3 hours of care. Among the 192 participants enrolled, 89 (46%) were White, (median age, 36 years; interquartile range, 27 to 53 years), with 103 receiving ketamine and 89 receiving placebo. There was no difference in the proportion experiencing improved pain 30 minutes after treatment (46/103 [44.7%] ketamine versus 32/89 [36.0%] placebo; difference in proportions, 8.7%; 95% confidence interval, −5.1% to 22.5%; =.22) or at any time point through 3 hours. There was no difference in secondary outcomes or side effects. In our sample, we did not detect an analgesic benefit of adding 50 mg intranasal ketamine to fentanyl in out-of-hospital trauma patients.

中文翻译：

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院外鼻内氯胺酮作为芬太尼的辅助治疗急性创伤性疼痛：一项随机临床试验


评估与单独使用芬太尼相比，院外使用芬太尼和鼻内氯胺酮是否能改善受伤后的早期疼痛控制。我们于 2017 年 10 月至 2021 年 12 月进行了一项院外随机、安慰剂对照、盲法、平行组临床试验。参与者是男性，年龄在 18 至 65 岁之间，在到达医院之前接受芬太尼治疗急性创伤性疼痛，由城市消防紧急医疗服务机构治疗，并被运送到该地区唯一的成人 I 级创伤中心。参与者随机接受 50 mg 鼻内氯胺酮或安慰剂。主要结局是研究药物给药后 30 分钟在口头数字评定量表上自我描述的疼痛至少减少 2 分的比例，通过 95% 置信区间重叠评估。次要结局是前 3 小时护理的副作用、疼痛评分和额外的止痛药。在入组的 192 名参与者中，89 名 （46%） 是白人（中位年龄 36 岁;四分位距 27 至 53 岁），其中 103 名接受氯胺酮治疗，89 名接受安慰剂。治疗后 30 分钟疼痛改善的比例没有差异（氯胺酮为 46/103 [44.7%] 与安慰剂为 32/89 [36.0%];比例差异为 8.7%;95% 置信区间，-5.1% 至 22.5%;=.22）或在 3 小时内的任何时间点。次要结局或副作用没有差异。在我们的样本中，我们没有检测到在院外创伤患者中向芬太尼添加 50 mg 鼻内氯胺酮的镇痛效果。