From the Department of Anaesthesia, Royal National Orthopaedic Hospital, London, United Kingdom.
Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Anesth Analg. 2020 Oct;131(4):1102-1110. doi: 10.1213/ANE.0000000000005073.
High-flow nasal oxygen (HFNO) is increasingly being used in intensive care units for management of hypoxemia and respiratory failure. However, the effectiveness of HFNO for preventing hypoxemia in the intraoperative period is unclear. The purpose of this systematic review was to compare patient oxygenation and end-tidal CO2 (EtCO2), between HFNO and conventional oxygenation, during the intraoperative period in surgical patients.
Standard databases were searched from inception to February 2020. Studies involving intraoperative use of HFNO with 1 of the 4 outcomes: (1) oxygen (O2) desaturation, (2) minimum O2 saturation, (3) safe apnea time, or (4) EtCO2 were included. Intraoperative period was divided into 2 phases: at induction with general anesthesia and during surgical procedure under sedation without tracheal intubation.
Eight randomized controlled trials (RCTs; 4 induction, 4 procedure, 2314 patients) were included for systematic review and meta-analyses. We found the risk of intraoperative O2 desaturation was lower in HFNO versus conventional oxygenation control group; at induction with an odds ratio (OR; 95% confidence interval [CI]) of 0.06 (0.01-0.59, P = .02), and during procedure, OR (95% CI) of 0.09 (0.05-0.18; P < .001). The minimum O2 saturation was higher in HFNO versus conventional oxygenation; at induction by a mean difference (MD) (95% CI) of 5.1% (3.3-6.9; P < .001), and during procedure, by a MD (95% CI) of 4.0% (1.8-6.2; P < .001). Safe apnea time at induction was longer in HFNO versus conventional oxygenation by a MD (95% CI) of 33.4 seconds (16.8-50.1; P < .001). EtCO2 at induction was not significantly different between HFNO and conventional oxygenation groups.
This systematic review and meta-analysis show that, in the intraoperative setting, HFNO compared to conventional oxygenation reduces the risk of O2 desaturation, increases minimum O2 saturation, and safe apnea time. HFNO should be considered for anesthesia induction and during surgical procedures under sedation without tracheal intubation in patients at higher risk of hypoxemia.
高流量鼻氧（HFNO）在重症监护病房中越来越多地用于管理低氧血症和呼吸衰竭。然而，HFNO 在手术期间预防低氧血症的效果尚不清楚。本系统评价的目的是比较 HFNO 与常规氧合在手术患者术中期间的患者氧合和呼气末二氧化碳（EtCO2）。
从成立到 2020 年 2 月，标准数据库进行了搜索。纳入术中使用 HFNO 的研究，有 4 项结果之一：（1）氧（O2）饱和度下降，（2）最低 O2 饱和度，（3）安全的窒息时间，或（4）EtCO2。术中期间分为两个阶段：全麻诱导期和镇静无气管插管手术期。
纳入 8 项随机对照试验（RCT；4 项诱导，4 项手术，2314 例患者）进行系统评价和荟萃分析。我们发现 HFNO 与常规氧合对照组相比，术中 O2 饱和度下降的风险较低；在诱导时的比值比（OR；95%置信区间[CI]）为 0.06（0.01-0.59，P =.02），而在手术期间，OR（95%CI）为 0.09（0.05-0.18；P <.001）。HFNO 与常规氧合相比，最低 O2 饱和度更高；在诱导时的平均差异（MD）（95%CI）为 5.1%（3.3-6.9；P <.001），在手术期间，MD（95%CI）为 4.0%（1.8-6.2；P <.001）。HFNO 诱导时的安全窒息时间比常规氧合长，MD（95%CI）为 33.4 秒（16.8-50.1；P <.001）。HFNO 与常规氧合组之间诱导时的 EtCO2 无显著差异。
本系统评价和荟萃分析表明，在手术期间，与常规氧合相比，HFNO 降低了 O2 饱和度下降的风险，增加了最低 O2 饱和度，并延长了安全的窒息时间。在低氧血症风险较高的患者中，HFNO 应考虑用于麻醉诱导和镇静无气管插管手术期间。
