NEJM:心脏停搏后昏迷幸存者的氧合目标

BACKGROUND

The appropriate oxygenation target for mechanical ventilation in comatose survivors of out-of-hospital cardiac arrest is unknown.

对于院外心脏停搏后的昏迷幸存者，机械通气的合适氧合目标尚不清楚。

METHODS

In this randomized trial with a 2-by-2 factorial design, we randomly assigned co- matose adults with out-of-hospital cardiac arrest in a 1:1 ratio to either a restrictive oxygen target of a partial pressure of arterial oxygen (Pao2) of 9 to 10 kPa (68 to 75mmHg) or a liberal oxygen target of a Pao2 of 13 to 14 kPa (98 to 105 mmHg); patients were also assigned to one of two blood-pressure targets (reported separately). The primary outcome was a composite of death from any cause or hospital discharge with severe disability or coma (Cerebral Performance Category [CPC] of 3 or 4; categories range from 1 to 5, with higher values indicating more severe disability), whichever occurred first within 90 days after randomization. Secondary outcomes were neuron-specific enolase levels at 48 hours, death from any cause, the score on the Montreal Cognitive Assessment (ranging from 0 to 30, with higher scores indicating better cognitive ability), the score on the modified Rankin scale (ranging from 0 to 6, with higher scores indicating greater disability), and the CPC at 90 days.

在此项2×2析因设计的随机试验中，我们以1:1的比例将院外心脏停搏后的昏迷成人随机分组，两组分别采用动脉氧分压（Pao₂）9~10 kPa（68~75 mm Hg）的限制性氧合目标和Pao₂ 13~14 kPa（98~105 mm Hg）的宽松氧合目标；患者还被分配到两个血压目标之一（在另外一篇论文中报告结果）。主要结局是由90日内的全因死亡或出院时严重失能或昏迷（脑功能分类[Cerebral Performance Category，CPC]3或4；分类范围，1~5，数值较高表明失能较严重）（以先发生的一项为准）构成的复合结局。次要结局是48小时的神经元特异性烯醇化酶水平、全因死亡、90日时的蒙特利尔认知评估评分（Montreal Cognitive Assessment，范围，0~30，评分较高表明认知能力较好）、改良Rankin量表评分（范围，0~6分，评分较高表明失能较严重）以及CPC。

RESULTS

A total of 789 patients underwent randomization. A primary-outcome event occurred in 126 of 394 patients (32.0%) in the restrictive-target group and in 134 of 395 pa- tients (33.9%) in the liberal-target group (hazard ratio, 0.95; 95% confidence inter- val, 0.75 to 1.21; P=0.69). At 90 days, death had occurred in 113 patients (28.7%) in the restrictive-target group and in 123 (31.1%) in the liberal-target group. On the CPC, the median category was 1 in the two groups; on the modified Rankin scale, the median score was 2 in the restrictive-target group and 1 in the liberal- target group; and on the Montreal Cognitive Assessment, the median score was 27 in the two groups. At 48 hours, the median neuron-specific enolase level was 17 μg per liter in the restrictive-target group and 18 μg per liter in the liberal- target group. The incidence of adverse events was similar in the two groups.

共计789例患者接受了随机分组。限制性目标组394例患者中的126例（32.0%）和宽松目标组395例患者中的134例（33.9%）发生了主要结局事件（风险比，0.95；95%置信区间，0.75~1.21；P=0.69）。90日时，限制性目标组113例患者（28.7%）和宽松目标组123例患者（31.1%）已死亡。在CPC方面，两组的中位分类均为1；在改良Rankin量表评分方面，限制性目标组的中位评分为2分，宽松目标组为1分；在蒙特利尔认知评估评分方面，两组的中位评分均为27分。在48小时，限制性目标组的中位神经元特异性烯醇化酶水平为17 μg/L，宽松目标组为18 μg/L。两组的不良事件发生率相似。

CONCLUSIONS

Targeting of a restrictive or liberal oxygenation strategy in comatose patients after resuscitation for cardiac arrest resulted in a similar incidence of death or severe disability or coma. (Funded by the Novo Nordisk Foundation; BOX ClinicalTrials .gov number, NCT03141099.)

对于心脏停搏后复苏成功的昏迷患者，限制性或宽松氧合目标策略导致了相似的死亡或者严重失能或昏迷发生率。（由诺和诺德基金会[Novo Nordisk Foundation]资助；BOX在ClinicalTrials.gov注册号为NCT03141099。）