Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Division of Intensive Care, Department of Anaesthesiology, Intensive Care, and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Resuscitation. 2023 Jan;182:109656. doi: 10.1016/j.resuscitation.2022.11.022. Epub 2022 Dec 5.
Perfusion pressure and chest compression quality are generally considered key determinants of brain oxygenation during cardiopulmonary resuscitation (CPR) and the impact of oxygen administration is less clear. We compared ventilation with 100% and 50% oxygen during ineffective manual chest compressions and hypothesized that 100% oxygen would improve brain oxygenation.
Ventricular fibrillation (VF) was induced electrically in anaesthetized pigs and left untreated for 5 minutes, followed by randomization to ineffective manual CPR with ventilation of 50% or 100% oxygen. The first defibrillation was performed 10 minutes after induction of VF, and CPR continued with mechanical chest compressions (LUCAS2™) and defibrillation every 2 minutes until 36 minutes or return of spontaneous circulation (ROSC). Brain oxygenation was measured with near-infrared spectroscopy (rSO) and invasive brain tissue oxygen (PbtO) with a probe (NEUROVENT-PTO, RAUMEDIC) inserted into frontal brain tissue. Cerebral oxygenation was compared between groups with Mann-Whitney U tests and linear mixed models.
Twenty-eight pigs were included in the study: 14 subjects in each group. During ineffective chest compressions relative PbtO was higher in the group ventilated with 100% compared to 50% oxygen (5.2 mmHg [1.4-20.5] vs 2.2 [0.8-6.8], p = 0.001), but there was no difference in rSO (22% [16-28] vs 18 [15-25], p = 0.090). The use of 50% or 100% oxygen showed no difference in relative PbtO (p = 1.00) and rSO (p = 0.206) during mechanical CPR.
The use of 100% compared to 50% oxygen during ineffective manual CPR improved brain oxygenation measured invasively in brain tissue, but there was no difference in rSO.
在心肺复苏（CPR）期间，灌注压和胸外按压质量通常被认为是脑氧合的关键决定因素，而给氧的影响则不太清楚。我们比较了在无效手动胸外按压期间使用 100%和 50%氧气进行通气，并假设 100%氧气会改善脑氧合。
在麻醉猪中诱发心室颤动（VF），并在未治疗的情况下放置 5 分钟，然后随机分配至 50%或 100%氧气通气的无效手动 CPR。VF 诱导后 10 分钟进行首次除颤，然后继续进行机械胸外按压（LUCAS2™）和每 2 分钟除颤，直到 36 分钟或自发循环恢复（ROSC）。使用近红外光谱（rSO）和插入额部脑组织的探头（NEUROVENT-PTO，RAUMEDIC）测量脑氧合。使用 Mann-Whitney U 检验和线性混合模型比较组间的脑氧合。
28 头猪被纳入研究：每组 14 头。在无效的胸外按压期间，用 100%氧气通气的组与用 50%氧气通气的组相比，相对 PbtO 更高（5.2mmHg[1.4-20.5] vs 2.2mmHg[0.8-6.8]，p=0.001），但 rSO 没有差异（22%[16-28] vs 18%[15-25]，p=0.090）。在机械 CPR 期间，使用 50%或 100%氧气在相对 PbtO（p=1.00）和 rSO（p=0.206）方面没有差异。
与 50%氧气相比，在无效的手动 CPR 期间使用 100%氧气可改善脑组织中测量的脑氧合，但 rSO 没有差异。
