Elmer Jonathan, Wang Bo, Melhem Samer, Pullalarevu Raghavesh, Vaghasia Nishit, Buddineni Jaya, Rosario Bedda L, Doshi Ankur A, Callaway Clifton W, Dezfulian Cameron
Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, 100 Hill Building, 3434 Fifth Avenue, Pittsburgh, PA, 15260, USA.
Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, USA.
Crit Care. 2015 Mar 10;19(1):105. doi: 10.1186/s13054-015-0824-x.
Post-cardiac arrest patients are often exposed to 100% oxygen during cardiopulmonary resuscitation and the early post-arrest period. It is unclear whether this contributes to development of pulmonary dysfunction or other patient outcomes.
We performed a retrospective cohort study including post-arrest patients who survived and were mechanically ventilated at least 24 hours after return of spontaneous circulation. Our primary exposure of interest was inspired oxygen, which we operationalized by calculating the area under the curve of the fraction of inspired oxygen (FiO₂AUC) for each patient over 24 hours. We collected baseline demographic, cardiovascular, pulmonary and cardiac arrest-specific covariates. Our main outcomes were change in the respiratory subscale of the Sequential Organ Failure Assessment score (SOFA-R) and change in dynamic pulmonary compliance from baseline to 48 hours. Secondary outcomes were survival to hospital discharge and Cerebral Performance Category at discharge.
We included 170 patients. The first partial pressure of arterial oxygen (PaO₂):FiO₂ ratio was 241 ± 137, and 85% of patients had pulmonary failure and 55% had cardiovascular failure at presentation. Higher FiO₂AUC was not associated with change in SOFA-R score or dynamic pulmonary compliance from baseline to 48 hours. However, higher FiO₂AUC was associated with decreased survival to hospital discharge and worse neurological outcomes. This was driven by a 50% decrease in survival in the highest quartile of FiO₂AUC compared to other quartiles (odds ratio for survival in the highest quartile compared to the lowest three quartiles 0.32 (95% confidence interval 0.13 to 0.79), P = 0.003).
Higher exposure to inhaled oxygen in the first 24 hours after cardiac arrest was not associated with deterioration in gas exchange or pulmonary compliance after cardiac arrest, but was associated with decreased survival and worse neurological outcomes.
心脏骤停后患者在心肺复苏期间及心脏骤停后的早期常吸入100%的氧气。目前尚不清楚这是否会导致肺功能障碍或其他患者预后情况。
我们进行了一项回顾性队列研究，纳入心脏骤停后存活且自主循环恢复后接受机械通气至少24小时的患者。我们感兴趣的主要暴露因素是吸入氧，通过计算每位患者24小时内吸入氧分数（FiO₂）曲线下面积来实现。我们收集了基线人口统计学、心血管、肺部及心脏骤停特异性协变量。我们的主要结局是序贯器官衰竭评估评分（SOFA-R）呼吸子量表的变化以及从基线到48小时动态肺顺应性的变化。次要结局是出院生存率和出院时的脑功能分级。
我们纳入了170例患者。首次动脉血氧分压（PaO₂）:FiO₂比值为241±137，85%的患者在就诊时有肺功能衰竭，55%的患者有心血管功能衰竭。较高的FiO₂曲线下面积与从基线到48小时SOFA-R评分或动态肺顺应性的变化无关。然而，较高的FiO₂曲线下面积与出院生存率降低和更差的神经学结局相关。这是由于FiO₂曲线下面积最高四分位数的患者生存率相比其他四分位数降低了50%（最高四分位数与最低三分位数相比的生存比值比为0.32（95%置信区间0.13至0.79），P = 0.003）。
心脏骤停后最初24小时内较高的吸入氧暴露与心脏骤停后气体交换或肺顺应性恶化无关，但与生存率降低和更差的神经学结局相关。
