Cumulative Epinephrine Dose during Cardiopulmonary Resuscitation and Neurologic Outcome

BACKGROUND: Epinephrine is the drug of choice in advanced cardiac life support, but it can have deleterious side effects after restoration of spontaneous circulation. OBJECTIVE: To investigate the association between the cumulative epinephrine dose used in advanced cardiac life support and neurologic outcome after cardiac arrest. DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: Adults admitted to the emergency department with witnessed, nontraumatic, normothermic ventricular fibrillation cardiac arrest and unsuccessful initial defibrillation. MEASUREMENTS: Functional neurologic outcome was regularly assessed by cerebral performance category (CPC) within 6 months after cardiac arrest. A CPC of 1 or 2 was defined as favorable recovery. RESULTS: Among 178 enrolled patients, the median cumulative epinephrine dose administered was 4 mg (range, 0 to 50 mg). In 151 patients (84%), spontaneous circulation was restored; 63 of these 151 patients (42%) had favorable neurologic recovery. Patients with an unfavorable CPC received a significantly higher cumulative dose of epinephrine than did patients with a favorable CPC (4 mg compared with 1 mg; P < 0.001). This finding persisted after stratification by duration of resuscitation. After possible cofounders were controlled for, the cumulative epinephrine dose remained an independent predictor of unfavorable neurologic outcome. CONCLUSIONS: The results indicate that an increasing cumulative dose of epinephrine administered during resuscitation is independently associated with unfavorable neurologic outcome after ventricular fibrillation cardiac arrest.