Background

Ventricular fibrillation (VF) waveform measures reflect myocardial physiologic status. Continuous assessment of VF prognosis using such measures could guide resuscitation, but has not been possible due to CPR artifact in the ECG. A recently-validated VF measure (termed VitalityScore), which estimates the probability (0-100%) of return-of-rhythm (ROR) after shock, can assess VF during CPR, suggesting potential for continuous application during resuscitation.

Objective

We evaluated VF using VitalityScore to characterize VF prognostic status continuously during resuscitation.

Methods

We characterized VF using VitalityScore during 60 seconds of CPR and 10 seconds of subsequent pre-shock CPR interruption in patients with out-of-hospital VF arrest. VitalityScore utility was quantified using area under the receiver operating characteristic curve (AUC). VitalityScore trends over time were estimated using mixed-effects models, and associations between trends and ROR were evaluated using logistic models. A sensitivity analysis characterized VF during protracted (100-second) periods of CPR.

Results

We evaluated 724 VF episodes among 434 patients. After an initial decline from 0-8 seconds following VF onset, VitalityScore increased slightly during CPR from 8-60 seconds (slope: 0.18 %/min). During the first 10 seconds of subsequent pre-shock CPR interruption, VitalityScore declined (slope: -14 %/min). VitalityScore predicted ROR throughout CPR with AUCs 0.73-0.75. Individual VitalityScore trends during 8-60 seconds of CPR were marginally associated with subsequent ROR (adjusted odds ratio for interquartile slope change (OR)=1.10, p=0.21), and became significant with protracted (≥100 seconds) CPR duration (OR=1.28, p=0.006).

Conclusion

VF prognostic status can be continuously evaluated during resuscitation, a development that could translate to patient-specific resuscitation strategies.

中文翻译：

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CPR 期间心室颤动预后状态的持续评估：对复苏的影响

背景

心室颤动 (VF) 波形测量反映心肌生理状态。使用此类措施持续评估 VF 预后可以指导复苏，但由于心电图中的 CPR 伪影而无法实现。最近验证的 VF 测量（称为VitalityScore）估计了休克后心律恢复 (ROR) 的概率 (0-100%)，可以在CPR 期间评估 VF，表明在复苏期间持续应用的潜力。

客观的

我们使用VitalityScore评估 VF，以在复苏期间持续表征 VF 预后状态。

方法

我们在院外 VF 骤停患者的 60 秒 CPR 和随后 10 秒的电击前 CPR 中断期间使用VitalityScore对 VF 进行了表征。VitalityScore效用使用接受者操作特征曲线 (AUC) 下的面积进行量化。使用混合效应模型估计VitalityScore随时间变化的趋势，并使用逻辑模型评估趋势和 ROR 之间的关联。一项敏感性分析表征了 CPR 延长（100 秒）期间的 VF。

结果

我们评估了 434 名患者中的 724 次 VF 发作。在 VF 发作后从 0-8 秒初始下降后，VitalityScore在 CPR 期间从 8-60 秒略有增加（斜率：0.18 %/min）。在随后的电击前 CPR 中断的前 10 秒内，VitalityScore下降（斜率：-14 %/min）。VitalityScore预测整个 CPR 的 ROR，AUC 为 0.73-0.75。CPR 8-60 秒期间的个体VitalityScore趋势与随后的 ROR （四分位间斜率变化的调整优势比 (OR) = 1.10，p = 0.21）略微相关，并且随着 CPR 持续时间延长（≥100 秒）变得显着（OR = 1.28，p = 0.006）。

结论

可以在复苏过程中持续评估 VF 的预后状态，这一发展可以转化为针对患者的复苏策略。