Communications Engineering Department, University of the Basque Country UPV/EHU, Ingeniero Torres Quevedo Plaza, 1, 48013 Bilbao, Spain.
Communications Engineering Department, University of the Basque Country UPV/EHU, Ingeniero Torres Quevedo Plaza, 1, 48013 Bilbao, Spain.
Resuscitation. 2019 May;138:74-81. doi: 10.1016/j.resuscitation.2019.02.028. Epub 2019 Mar 2.
Unsuccessful defibrillation shocks adversely affect survival from out-of-hospital cardiac arrest (OHCA). Ventricular fibrillation (VF) waveform analysis is the tool-of-choice for the non-invasive prediction of shock success, but surrogate markers of perfusion like end-tidal CO (EtCO) could improve the prediction. The aim of this study was to evaluate EtCO as predictor of shock success, both individually and in combination with VF-waveform analysis.
In total 514 shocks from 214 OHCA patients (75 first shocks) were analysed. For each shock three predictors of defibrillation success were automatically calculated from the device files: two VF-waveform features, amplitude spectrum area (AMSA) and fuzzy entropy (FuzzyEn), and the median EtCO (MEtCO) in the minute before the shock. Sensitivity, specificity, receiver operating characteristic (ROC) curves and area under the curve (AUC) were calculated, for each predictor individually and for the combination of MEtCO and VF-waveform predictors. Separate analyses were done for first shocks and all shocks.
MEtCO in first shocks was significantly higher for successful than for unsuccessful shocks (31mmHg/25mmHg, p<0.05), but differences were not significant for all shocks (32mmHg/29mmHg, p>0.05). MEtCO predicted shock success with an AUC of 0.66 for first shocks, but was not a predictor for all shocks (AUC 0.54). AMSA and FuzzyEn presented AUCs of 0.76 and 0.77 for first shocks, and 0.75 and 0.75 for all shocks. For first shocks, adding MEtCO improved the AUC of AMSA and FuzzyEn to 0.79 and 0.83, respectively.
MEtCO predicted defibrillation success only for first shocks. Adding MEtCO to VF-waveform analysis in first shocks improved prediction of shock success. VF-waveform features and MEtCO were automatically calculated from the device files, so these methods could be introduced in current defibrillators adding only new software.
无效除颤电击会对院外心脏骤停（OHCA）患者的生存产生不利影响。心室颤动（VF）波形分析是预测电击成功的首选工具，但像呼气末 CO（EtCO）这样的灌注替代标志物可能会提高预测准确性。本研究旨在评估 EtCO 作为电击成功预测因子的作用，包括单独使用以及与 VF 波形分析联合使用。
共分析了 214 例 OHCA 患者（75 例为首次电击）的 514 次电击。对于每一次电击，从设备文件中自动计算出三个预测电击成功的指标：两个 VF 波形特征，即幅度谱面积（AMSA）和模糊熵（FuzzyEn），以及电击前一分钟的平均 EtCO（MEtCO）。计算了每个预测因子单独使用以及 MEtCO 和 VF 波形预测因子联合使用的灵敏度、特异性、受试者工作特征（ROC）曲线和曲线下面积（AUC）。分别对首次电击和所有电击进行了单独分析。
首次电击中，成功电击的 MEtCO 显著高于不成功电击（31mmHg/25mmHg，p<0.05），但所有电击之间差异无统计学意义（32mmHg/29mmHg，p>0.05）。MEtCO 对首次电击的预测效能 AUC 为 0.66，但对所有电击无预测价值（AUC 0.54）。AMSA 和 FuzzyEn 的 AUC 分别为首次电击 0.76 和 0.77，所有电击 0.75 和 0.75。对于首次电击，将 MEtCO 加入到 AMSA 和 FuzzyEn 中可分别将 AUC 提高到 0.79 和 0.83。
MEtCO 仅能预测首次电击的除颤效果。在首次电击中，将 MEtCO 加入到 VF 波形分析中可提高电击成功的预测能力。VF 波形特征和 MEtCO 可从设备文件中自动计算，因此仅需增加新软件，即可将这些方法引入当前的除颤器中。
