氧化亚氮相关性术后恶心呕吐取决于暴露时间。

Nitrous oxide-related postoperative nausea and vomiting depends on duration of exposure.

机构信息

From the Department of Anaesthesia, Austin Health, Melbourne, Australia (P.J.P. and C.Y.W.); and Department of Surgery, Austin Hospital and University of Melbourne, Melbourne, Australia, and Institute for Breathing and Sleep, Victoria, Australia (P.J.P).

出版信息

Anesthesiology. 2014 May;120(5):1137-45. doi: 10.1097/ALN.0000000000000122.

DOI:10.1097/ALN.0000000000000122

PMID:24401771

Abstract

BACKGROUND

Inclusion of nitrous oxide in the gas mixture has been implicated in postoperative nausea and vomiting (PONV) in numerous studies. However, these studies have not examined whether duration of exposure was a significant covariate. This distinction might affect the future place of nitrous oxide in clinical practice.

METHODS

PubMed listed journals reporting trials in which patients randomized to a nitrous oxide or nitrous oxide-free anesthetic for surgery were included, where the incidence of PONV within the first 24 postoperative hours and mean duration of anesthesia was reported. Meta-regression of the log risk ratio for PONV with nitrous oxide (lnRR PONVN2O) versus duration was performed.

RESULTS

Twenty-nine studies in 27 articles met the inclusion criteria, randomizing 10,317 patients. There was a significant relationship between lnRR PONVN2O and duration (r = 0.51, P = 0.002). Risk ratio PONV increased 20% per hour of nitrous oxide after 45 min. The number needed to treat to prevent PONV by avoiding nitrous oxide was 128, 23, and 9 where duration was less than 1, 1 to 2, and over 2 h, respectively. The risk ratio for the overall effect of nitrous oxide on PONV was 1.21 (CIs, 1.04-1.40); P = 0.014.

CONCLUSIONS

This duration-related effect may be via disturbance of methionine and folate metabolism. No clinically significant effect of nitrous oxide on the risk of PONV exists under an hour of exposure. Nitrous oxide-related PONV should not be seen as an impediment to its use in minor or ambulatory surgery.

摘要

背景

在许多研究中，一氧化二氮（N2O）气体混合物的使用与术后恶心呕吐（PONV）有关。然而，这些研究并未检查暴露时间是否是一个重要的协变量。这一区别可能会影响 N2O 在未来临床实践中的地位。

方法

PubMed 列出了报告将患者随机分配到接受含 N2O 或不含 N2O 的麻醉用于手术的试验的期刊，报告了术后 24 小时内 PONV 的发生率和麻醉的平均持续时间。对 N2O 与 PONV 的对数风险比（lnRR PONVN2O）与持续时间进行了元回归分析。

结果

27 篇文章中的 29 项研究符合纳入标准，共纳入了 10317 名患者。lnRR PONVN2O 与持续时间之间存在显著关系（r = 0.51，P = 0.002）。在 45 分钟后，N2O 每增加 1 小时，风险比 PONV 增加 20%。在持续时间小于 1 小时、1 至 2 小时和超过 2 小时的情况下，为避免 N2O 而预防 PONV 的需要治疗人数分别为 128、23 和 9。N2O 对 PONV 总体影响的风险比为 1.21（CI，1.04-1.40）；P = 0.014。