Summary of GRADE evidence profile.

BackgroundNitrous oxide (N2O) with rapid analgesic effect is often used to relieve pain induced by diagnostic procedures. This review was conducted to evaluate the efficacy and safety of N2O in patients undergoing puncture biopsy.MethodsWe systematically searched PubMed, Embase, the Cochrane Library, Web of Science, Scopus and the ClinicalTrials.gov up to March, 2022. Randomized controlled trials (RCTs) were included if they investigated the effect of N2O in adults undergoing puncture biopsy. The primary outcome was pain score. Secondary outcomes included anxiety score, patient satisfaction and side effects.ResultsTwelve RCTs with 1070 patients were included in the qualitative review, of which eleven RCTs were included in the meta-analysis. Pooled analysis suggested that compared with the controls (placebo, lidocaine and midazolam), N2O had better analgesic effect (MD -1.12, 95% CI -2.12 to -0.13, P = 0.03; I2 = 94%). In addition, N2O significantly alleviated patient anxiety (MD = -1.79, 95% CI -2.41 to -1.18, P2 = 0%) and improved patient satisfaction (MD 1.81, 95% CI 0.11 to 3.50, P = 0.04; I2 = 92%). There was no significant difference regrading the risk of nausea (RR 2.56; 95% CI 0.70 to 9.31, P = 0.15; I2 = 0%), headache (RR 0.62, 95% CI 0.17 to 2.33, P = 0.48; I2 = 46%), dizziness (RR 1.80, 95% CI 0.63 to 5.13, P = 0.27; I2 = 0%) or euphoria (RR 2.67, 95% CI 0.81 to 8.79, P = 0.11; I2 = 8%) between the N2O group and the control group.ConclusionThe present review suggested that N2O might be effective for pain management in patients undergoing puncture biopsy.

背景：一氧化二氮（Nitrous oxide, N₂O）具备快速镇痛效应，常被用于缓解诊断操作引发的疼痛。本综述旨在评估一氧化二氮在接受穿刺活检患者中的有效性与安全性。
方法：本研究于2022年3月前系统检索了PubMed、Embase、考克兰图书馆（Cochrane Library）、Web of Science、Scopus及ClinicalTrials.gov数据库。纳入针对接受穿刺活检的成人患者中一氧化二氮作用效果的随机对照试验（Randomized Controlled Trial, RCT）。主要结局指标为疼痛评分，次要结局指标包括焦虑评分、患者满意度及不良反应。
结果：本定性综述共纳入12项随机对照试验，涉及1070例患者，其中11项试验被纳入荟萃分析。合并分析结果显示，与对照组（安慰剂、利多卡因及咪达唑仑）相比，一氧化二氮具有更优的镇痛效果（均差Mean Difference, MD=-1.12，95%置信区间Confidence Interval, CI：-2.12~-0.13，P=0.03；I²=94%）。此外，一氧化二氮可显著缓解患者焦虑情绪（MD=-1.79，95%CI：-2.41~-1.18，P=0%）并提升患者满意度（MD=1.81，95%CI：0.11~3.50，P=0.04；I²=92%）。一氧化二氮组与对照组在恶心（相对风险Relative Risk, RR=2.56，95%CI：0.70~9.31，P=0.15；I²=0%）、头痛（RR=0.62，95%CI：0.17~2.33，P=0.48；I²=46%）、头晕（RR=1.80，95%CI：0.63~5.13，P=0.27；I²=0%）及欣快症（RR=2.67，95%CI：0.81~8.79，P=0.11；I²=8%）的发生风险上均无显著差异。
结论：本综述表明，一氧化二氮或可有效用于接受穿刺活检患者的疼痛管理。