Background: Recent studies suggest that doses of epinephrine of 0.1 mg per kilogram of body weight or higher may improve myocardial and cerebral blood flow as well as survival in cardiac arrest. Such studies have called into question the traditional dose of epinephrine (0.007 to 0.014 mg per kilogram) recommended for advanced cardiac life support.
Methods: We randomly assigned 650 patients who had had cardiac arrest either in or outside the hospital to receive up to five doses of high-dose (7 mg) or standard-dose (1 mg) epinephrine at five-minute intervals according to standard protocols for advanced cardiac life support. Patients who collapsed outside the hospital received no advanced-life-support measures other than defibrillation before reaching the hospital.
Results: There was no significant difference between the high-dose group (n = 317) and the standard-dose group (n = 333) in the proportions of patients who survived for one hour (18 percent vs. 23 percent, respectively) or who survived until hospital discharge (3 percent vs. 5 percent). Among the survivors, there was no significant difference in the proportions who remained in the best category of cerebral performance (90 percent vs. 94 percent) and no significant difference in the median Mini-Mental State score (36 vs. 37). The exploration of clinically important subgroups, including those with out-of-hospital arrest (n = 335) and those with in-hospital arrest (n = 315), failed to identify any patients who appeared to benefit from high-dose epinephrine and suggested that some patients may have worse outcomes after high-dose epinephrine.
Conclusion: High-dose epinephrine was not found to improve survival or neurologic outcomes in adult victims of cardiac arrest.