Abstract P50: Quantitative Waveform Measures of Ventricular Fibrillation Predict Return of Spontaneous Circulation and Short-term Survival
Background: VF ECG quantitative waveform measures (QWM) correlate with ROSC and short-term survival. We applied 5 QWM to VF ECG data from a study comparing cardiocerebral to standard cardiopulmonary resuscitation (CCR vs. CPR) using a swine model of prolonged VF to determine if these QWM would reliably predict ROSC and 20-minute survival.
Methods: The study was IACUC approved. The 48 animals were instrumented under anesthesia. Lead II ECG data were digitally recorded. VF was electrically induced. After 10″ of untreated VF, 24 controls received standard CPR [100/minute mechanical chest compressions (MCC) with 30:2 ventilations] in a manner consistent with clinical practice. The CCR group had continuous uninterrupted MCC at 100/minute and no active ventilations. Both groups received epinephrine followed by 2.5″ of MCC before the first 120J RS attempt. After successful RS, standardized post-resuscitative care was provided to a 20-minute endpoint. All failed RS were followed by repeat doses of epinephrine every 3″, continued MCC with 30:2 ventilations, and RS every minute as long as a shockable rhythm persisted. Five-second epochs of VF ECG after 10″ of untreated VF and just prior to RS1 were used to calculate 5 QWM: logarithm of the absolute correlations (LAC); median slope (MS); angular velocity (AV); amplitude spectrum area (AMSA); and frequency ratio (FR). The QWM were compared by ANOVA for ROSC and survival and the area under the ROC curves were calculated.
Results: The CPR group had no improvement in QWM between samples 1 and 2: AV p=0.10, AMSA p=0.07, MS p=0.31, LAC change was a decrease significant to p=0.005. The CCR group had marked improvement in all QWM between the 2 samples: AV p=0.002, AMSA p=0.004, MS p=0.0001, FR p=0.0004, and LAC increase p=0.066. ANOVA results are shown in table 1⇓. The ROC curves for MS, AMSA and AV achieved AUCs >0.90 for ROSC and >0.82 for survival.
Conclusion: These 5 QWM reliably predict ROSC and short-term survival in porcine VF.