全麻诱导前使用无创呼吸机进行预充氧：一项随机对照试验的系统回顾和荟萃分析

贵州医科大学    麻醉与心脏电生理课题组

翻译：张中伟  编辑：马艳燕  审校：曹莹

背景：预充氧对于在插管前为患者提供足够的氧气储备是至关重要的，能延长呼吸终止到氧饱和度开始下降之间的时间(安全呼吸暂停时间)。临床上，预充氧一般采用面罩通气方式。无创呼吸机通气法是一种新型的预充氧方法。本研究的目的是比较无创呼吸机和面罩通气在预充氧过程中的效果。

方法：在PubMed、Embase、Cochrane图书馆和ClinicalTrials.gov注册中心搜索从数据库建立到2021年9月发表的合格研究。对个体效应进行标准化，并使用随机效应模型进行荟萃分析，以计算合并效应。纳入标准为随机对照试验，比较无创呼吸机和面罩通气在择期手术的患者中预充氧的结果。主要观察指标是安全呼吸暂停时间，次要观察指标是患者术后并发症的发生率、预充氧3min后呼出氧浓度(FeO2)达到90%的患者数量，气管插管时最小SpO2，预充氧后动脉血氧分压(PaO2)和二氧化碳分压(PaCO2)，以及气管插管后PaO2和PaCO2。

结果：有13项试验符合纳入标准。两组在安全呼吸暂停时间、预充氧3min后呼出氧浓度（FeO2）达到90%的患者数量、预充氧及气管插管后PaO2、PaCO2的比较，差异均有统计学意义。在非肥胖亚组，两组患者的安全呼吸暂停时间无显著差异(平均差：125.38，95%置信区间：−12.26~263.03)。

结论：无创呼吸机预充氧似乎比传统的面罩通气法更有效。根据研究结果，我们建议使用无创呼吸机进行预充氧。

原始文献来源：Tsai-Lien Chiang, Ka-Wai Tam, Jui-Tai Chen,et al. Non-invasive ventilation for preoxygenation before general anesthesia: a systematic review and meta-analysis of randomized controlled trials[J]. BMC Anesthesiology (2022) 22:306

      英文原文      

Non-invasive ventilation for preoxygenation before general anesthesia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND：Preoxygenation is crucial for providing sufficient oxygen reservoir to a patient before intubation and enables the extension of the period between breathing termination and critical desaturation (safe apnoea time). Conventionally, face mask ventilation is used for preoxygenation. Non-invasive ventilation is a new preoxygenation method. The study objective was to compare the outcomes of non-invasive ventilation and face mask ventilation for preoxygenation.

Methods: PubMed, Embase, Cochrane Library, and the ClinicalTrials.gov registry were searched for eligible studies published from database inception to September 2021. Individual effect sizes were standardized, and a meta‑analysis was conducted using random effects models to calculate the pooled effect size. Inclusion criteria were randomised controlled trials of comparing the outcomes of non‑invasive ventilation or face mask ventilation for preoxygenation in patients scheduled for surgeries. The primary outcome was safe apnea time, and the secondary outcomes were post‑operative complications, number of patients who achieved the expired  O2 fraction  (FeO2) after 3 min of preoxy‑genation, minimal  SpO2 during tracheal intubation, partial pressure of oxygen in the arterial blood  (PaO2) and partial

pressure of carbon dioxide  (PaCO2) after preoxygenation, and  PaO2 and  PaCO2 after tracheal intubation.

RESULTS：13 trials were eligible for inclusion in this study. Significant differences were observed in safe apnoea time, number of patients who achieved  FeO2 90% after preoxygenation for 3 min, and  PaO2 and  PaCO2 after preoxygenation and tracheal intubation. Only in the non‑obese subgroup, no significant difference was observed in safe apnoea time (mean difference: 125.38, 95% confidence interval: − 12.26 to 263.03).

CONCLUSION：Non-invasive ventilation appeared to be more effective than conventional methods for preoxygenation. We recommend non‑invasive ventilation based on our results