Kawakami Hiromasa, Mihara Takahiro, Nakamura Nobuhito, Ka Koui, Goto Takahisa
From the Department of Anesthesiology, Kanagawa Children's Medical Center, Yokohama, Japan.
Department of Anesthesiology and Critical Care Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
Anesth Analg. 2017 Dec;125(6):2072-2080. doi: 10.1213/ANE.0000000000002453.
Caudal anesthesia has been used for postoperative pain control in pediatric surgical patients, but the duration of the analgesic effect is occasionally unsatisfactory. Intravenous steroids have been shown to be effective for postsurgical pain management after certain surgeries. The aim of this meta-analysis with trial sequential analysis (TSA) was to evaluate the analgesic effect of steroids in patients administered with caudal anesthesia.
This study was a systematic review and meta-analysis. A search of published literature was conducted in the MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials databases and in trial registration sites. Randomized controlled trials that compared intravenous steroids with a placebo in pediatric patients who had received caudal anesthesia for surgery were included in the study. The primary outcomes from the present meta-analysis were the analgesic duration and the number of patients who required rescue analgesics. The analgesic duration and incidence of rescue use were summarized using mean difference or risk ratio with a 97.5% confidence interval (CI), respectively. If the 97.5% CI of the mean difference or risk ratio included a value of 0 or 1, respectively, we considered the difference not to be significant. We used the random effects model to combine the results. Heterogeneity was quantified with the I statistic. The quality of the trials was evaluated using the Cochrane methodology. Moreover, a TSA with a risk of type 1 error of 2.5% and power of 90% was performed. We established the minimum clinically meaningful difference of analgesic duration as 3 hours. The target sample size for meta-analysis was also calculated in the TSA. We also assessed adverse events.
Six trials with 424 patients were included; 211 patients received intravenous steroids. All trials compared dexamethasone of at least 0.5 mg/kg dose with a placebo. Dexamethasone prolonged the duration of caudal analgesia (mean difference, 244 minutes; 97.5% CI, 188-300). Heterogeneity was considerable with an I value of 94.8%. Quality of evidence was very low. The TSA suggested that only 17.0% of the target sample size had been reached, but the cumulative Z score crossed the trial sequential monitoring boundary to indicate a benefit. Rescue use was reported in 4 studies with 260 patients. Rescue use was not significantly reduced in the dexamethasone group (risk ratio, 0.53; 97.5% CI, 0.09-3.30; I, 98.7%). No increase in adverse events was reported.
Intravenous dexamethasone prolongs the analgesic duration of caudal anesthesia. Trials to investigate the effectiveness of a lower dose of the dexamethasone in prolonging analgesic effects would be of interest. Further trials with a low risk of bias are necessary.
骶管阻滞麻醉已用于小儿外科手术患者的术后疼痛控制，但镇痛效果的持续时间有时并不理想。静脉注射类固醇已被证明在某些手术后的疼痛管理中有效。本项采用序贯试验分析（TSA）的荟萃分析旨在评估类固醇在接受骶管阻滞麻醉患者中的镇痛效果。
本研究为系统评价和荟萃分析。在MEDLINE、EMBASE、科学引文索引和Cochrane对照试验中央注册库数据库以及试验注册网站上检索已发表的文献。纳入在接受骶管阻滞麻醉进行手术的儿科患者中比较静脉注射类固醇与安慰剂的随机对照试验。本荟萃分析的主要结局为镇痛持续时间和需要补救性镇痛的患者数量。镇痛持续时间和补救性使用的发生率分别采用平均差或风险比及97.5%置信区间（CI）进行汇总。如果平均差或风险比的97.5%CI分别包含0或1，则认为差异无统计学意义。我们采用随机效应模型合并结果。异质性用I统计量进行量化。采用Cochrane方法评估试验质量。此外，还进行了1类错误风险为2.5%、检验效能为90%的TSA。我们将镇痛持续时间的最小临床有意义差异设定为3小时。在TSA中还计算了荟萃分析的目标样本量。我们还评估了不良事件。
纳入6项试验，共424例患者；211例患者接受静脉注射类固醇。所有试验均将至少0.5mg/kg剂量的地塞米松与安慰剂进行比较。地塞米松延长了骶管阻滞镇痛的持续时间（平均差为244分钟；97.5%CI为188 - 300）。异质性相当大，I值为94.8%。证据质量非常低。TSA表明仅达到目标样本量的17.0%，但累积Z分数越过序贯试验监测边界，表明存在益处。4项研究共260例患者报告了补救性使用情况。地塞米松组的补救性使用未显著减少（风险比为0.53；97.5%CI为0.09 - 3.30；I为98.7%）。未报告不良事件增加。
静脉注射地塞米松可延长骶管阻滞麻醉的镇痛持续时间。研究较低剂量地塞米松延长镇痛效果有效性的试验将很有意义。有必要进行偏倚风险较低的进一步试验。
