Abstract / Summary
The optimal epinephrine redosing interval during advanced life support remains uncertain. We randomized 48 Yorkshire pigs with ventricular fibrillation (VF) cardiac arrest to intravenous epinephrine 0.02 mg/kg every 1 or 3 min, with first defibrillation at 20 or 24 min. The primary outcome was 48-h survival; neurological assessment was blinded. Survival (70.8% vs 33.3%; P = 0.020) and sustained return of spontaneous circulation (ROSC) (75.0% vs 33.3%; P = 0.008) were higher with the 1-min regimen than with the 3-min regimen. After adjustment for first-defibrillation timing, the 1-min regimen was associated with a lower hazard of death within 48 h (hazard ratio, 0.32; 95% confidence interval [CI], 0.13–0.78), higher odds of sustained ROSC (odds ratio [OR], 5.40; 95% CI, 1.68–19.29), and a more favorable composite 48-h neurological deficit score, with deaths assigned 400 (common OR, 4.66; 95% CI, 1.49–15.90). Pressure–time integrals for systolic, diastolic, and mean blood pressure differed in rank-based but not permutation analyses. In this porcine model, the 1-min epinephrine dosing regimen was associated with higher 48-h survival and a more favorable composite 48-h neurological deficit score. However, clinical translation requires further study because dosing interval was inseparable from cumulative exposure and defibrillation timing was protocol-defined.