Group of Signal and Communications. University of the Basque Country, UPV/EHU Bilbao, Bizkaia, Spain.
Group of Signal and Communications. University of the Basque Country, UPV/EHU Bilbao, Bizkaia, Spain; Department of Applied Mathematics, University of the Basque Country, UPV/EHU Bilbao, Bizkaia, Spain.
Resuscitation. 2024 Jul;200:110259. doi: 10.1016/j.resuscitation.2024.110259. Epub 2024 May 31.
Interpretation of end-tidal CO (ETCO) during manual cardiopulmonary resuscitation (CPR) is affected by variations in ventilation and chest compressions. This study investigates the impact of standardising ETCO to constant ventilation rate (VR) and compression depth (CD) on absolute values and trends.
Retrospective study of out-of-hospital cardiac arrest cases with manual CPR, including defibrillator and clinical data. ETCO, VR and CD values were averaged by minute. ETCO was standardised to 10 vpm and 50 mm. We compared standardised (ET) and measured (ET) values and trends during resuscitation.
Of 1,036 cases, 287 met the inclusion criteria. VR was mostly lower than recommended, 8.8 vpm, and highly variable within and among patients. CD was mostly within guidelines, 49.8 mm, and less varied. ET was lower than ET by 7.3 mmHg. ET emphasized differences by sex (22.4 females vs. 25.6 mmHg males), initial rhythm (29.1 shockable vs. 22.7 mmHg not), intubation type (25.6 supraglottic vs. 22.4 mmHg endotracheal) and return of spontaneous circulation (ROSC) achieved (34.5 mmHg) vs. not (20.1 mmHg). Trends were different between non-ROSC and ROSC patients before ROSC (-0.3 vs. + 0.2 mmHg/min), and between sustained and rearrest after ROSC (-0.7 vs. -2.1 mmHg/min). Peak ET was higher for sustained than for rearrest (53.0 vs. 42.5 mmHg).
Standardising ETCO eliminates effects of VR and CD variations during manual CPR and facilitates comparison of values and trends among and within patients. Its clinical application for guidance of resuscitation warrants further investigation.
在手动心肺复苏（CPR）期间，潮气末二氧化碳（ETCO）的解读受通气和胸外按压变化的影响。本研究旨在探讨标准化 ETCO 至恒定通气率（VR）和按压深度（CD）对绝对值和趋势的影响。
回顾性研究了接受手动 CPR 的院外心脏骤停病例，包括除颤仪和临床数据。每分钟平均 ETCO、VR 和 CD 值。将 ETCO 标准化为 10 vpm 和 50mm。我们比较了复苏过程中标准化（ET）和测量（ET）值和趋势。
在 1036 例病例中，287 例符合纳入标准。VR 大多低于推荐值 8.8 vpm，且在患者内和患者间差异较大。CD 大多符合指南，为 49.8mm，且变化较小。ET 比 ET 低 7.3mmHg。ET 强调了性别（22.4 名女性 vs. 25.6mmHg 男性）、初始节律（29.1 可电击节律 vs. 22.7mmHg 非可电击节律）、插管类型（25.6 声门上 vs. 22.4 气管内）和自主循环恢复（ROSC）的差异（34.5mmHg）和未恢复（20.1mmHg）。在 ROSC 前，非 ROSC 和 ROSC 患者的趋势不同（-0.3 与+0.2mmHg/min），在 ROSC 后持续和再停搏患者之间的趋势也不同（-0.7 与-2.1mmHg/min）。持续患者的 ET 峰值高于再停搏患者（53.0 与 42.5mmHg）。
标准化 ETCO 消除了手动 CPR 期间 VR 和 CD 变化的影响，便于患者间和患者内的数值和趋势比较。其在复苏指导中的临床应用需要进一步研究。
