School of Nursing, Weifang Medical University, Weifang, China; Department of Stomatology, the 960th hospital of People's Liberation Army of China (PLA), Jinan, China.
School of Nursing, Naval Military Medical University, Shanghai, China.
Am J Emerg Med. 2022 Jun;56:92-99. doi: 10.1016/j.ajem.2022.03.028. Epub 2022 Mar 23.
Nitrous oxide (NO) has a rapidly analgesic effect, but evidence regarding its role in managing pain in adults in the emergency department (ED) is conflicting. The purpose of this meta-analysis is to investigate the analgesic efficacy and safety of NO in adults in ED.
We systematically searched PubMed, the Cochrane Library, Embase, Web of science, China National Knowledge Infrastrusture (CNKI) and Wanfang Database up to August 10th, 2021. Randomized controlled trials (RCTs) were included if they compared NO/O to placebo or other analgesic methods for management of pain in adults in ED or prehospital. The primary outcome was the analgesic efficacy of NO. Secondary outcomes included adverse events, satisfaction of patients and the duration of procedure.
14 RCTs with 1751 patients were included. Pooled analysis suggested that NO had better analgesia than placebo in the pain score (WMD = -3.00, 95% CI = -3.99 to -2.02, P < 0.00001, I = 91%) and the number of patients with pain relief (OR = 6.18, 95% CI = 3.22 to 11.85, P < 0.00001, I = 0%), while there were no significant difference in the pain score (WMD = 0.93, 95% CI = -1.09 to 2.95, P = 0.37, I = 97%) or the number of patients with pain relief (OR = 0.07, 95% CI = 0.00 to 3.47, P = 0.18, I = 86%) between the NO group and the other analgesic method group. Although NO did not increase nausea (OR = 1.52, 95% CI = 0.44 to 5.21, P = 0.50, I = 54%) or satisfaction of patients (OR = 1.06, 95% CI = 0.16 to 7.18, P = 0.96, I = 81%), it was associated with higher tendency of vomiting (OR = 6.50, 95% CI = 2.07 to 20.42, P = 0.001, I = 29%) and dizziness (OR = 4.54, 95% CI = 2.27 to 9.09, P < 0.0001, I = 26%), and shorter procedure time (WMD = -5.73 min, 95% CI = -10.14 min to -1.32 min, P = 0.01, I = 98%).
The present meta-analysis suggested that NO could provide better analgesia than placebo and similar analgesia to other methods with more vomiting and dizziness in adults in ED.
氧化亚氮（NO）具有快速镇痛作用，但关于其在急诊科（ED）成人疼痛管理中的作用的证据存在矛盾。本荟萃分析的目的是调查 NO 在 ED 成人中的镇痛疗效和安全性。
我们系统地检索了 PubMed、Cochrane 图书馆、Embase、Web of science、中国国家知识基础设施（CNKI）和万方数据库，截至 2021 年 8 月 10 日。如果随机对照试验（RCT）比较了 NO/O 与安慰剂或其他镇痛方法在 ED 或院前成人疼痛管理中的疗效，则将其纳入。主要结局是 NO 的镇痛效果。次要结局包括不良反应、患者满意度和操作时间。
纳入了 14 项 RCT 和 1751 名患者。荟萃分析表明，与安慰剂相比，NO 在疼痛评分（WMD = -3.00，95%CI = -3.99 至 -2.02，P < 0.00001，I = 91%）和缓解疼痛的患者数量（OR = 6.18，95%CI = 3.22 至 11.85，P < 0.00001，I = 0%）方面具有更好的镇痛效果，而在疼痛评分（WMD = 0.93，95%CI = -1.09 至 2.95，P = 0.37，I = 97%）或缓解疼痛的患者数量（OR = 0.07，95%CI = 0.00 至 3.47，P = 0.18，I = 86%）方面，NO 组与其他镇痛方法组之间无显著差异。尽管 NO 并未增加恶心（OR = 1.52，95%CI = 0.44 至 5.21，P = 0.50，I = 54%）或患者满意度（OR = 1.06，95%CI = 0.16 至 7.18，P = 0.96，I = 81%），但与更高的呕吐（OR = 6.50，95%CI = 2.07 至 20.42，P = 0.001，I = 29%）和头晕（OR = 4.54，95%CI = 2.27 至 9.09，P < 0.0001，I = 26%）发生率和更短的操作时间（WMD = -5.73 分钟，95%CI = -10.14 分钟至 -1.32 分钟，P = 0.01，I = 98%）相关。
本荟萃分析表明，NO 可提供比安慰剂更好的镇痛效果，与其他方法相似的镇痛效果，但在 ED 成人中引起更多呕吐和头晕。
