A RANDOMIZED, BLINDED TRIAL OF HIGH-DOSE EPINEPHRINE VERSUS STANDARD-DOSE EPINEPHRINE IN A SWINE MODEL OF PEDIATRIC ASPHYXIAL CARDIAC-ARREST

Objective: To determine whether high-dose epinephrine administration d uring cardiopulmonary resuscitation (CPR) in a swine pediatric asphyxi al cardiac arrest model improves outcome (i.e., resuscitation rate, su rvival rate, and neurologic function) compared with standard-dose epin ephrine. Design: A randomized, blinded study. Setting: A large animal cardiovascular laboratory at a university. Subjects: Thirty domestic p iglets (3 to 4 months of age) were randomized to receive standard-dose epinephrine (0.02 mg/kg) or high-dose epinephrine (0.2 mg/kg) during CPR after 10 mins of cardiac standstill with loss of aortic pulsation after endotracheal tube clamping. Interventions: Two minutes of CPR we re provided, followed by advanced pediatric life support, Successfully resuscitated animals were supported in an intensive care unit (ICU) s etting for 2 hrs and then observed for 24 hrs. Measurements and Main R esults: Electrocardiogram, thoracic aortic blood pressure, and right a trial blood pressure were monitored continuously until the intensive c are period ended. Survival rate and neurologic outcome were determined .Return of spontaneous circulation was obtained in 13 of 15 high-dose epinephrine piglets vs. ten of 15 standard-dose epinephrine piglets (p < .20). Four of 13 high-dose piglets died in the ICU period after ini tial resuscitation vs, 0 of ten standard dose piglets (p less than or equal to .05), Nine high dose piglets survived 2 hrs vs, ten standard dose piglets, Three piglets in each group survived for 24 hrs, but all were severely neurologically impaired. Two minutes after resuscitatio n, piglets treated with high-dose epinephrine had higher heart rates ( 210 +/- 24 vs, 189 +/- 40 beats/min, p < .05) and higher aortic diasto lic pressures (121 +/- 39 vs. 74 +/- 40 mm Hg, p < .01). Within 10 min s of return of spontaneous circulation, severe tachycardia (>240 beats /min) was more frequently noted in the high-dose group than in the sta ndard-dose group (p < .05). All four high dose piglets that died in th e ICU period experienced ventricular fibrillation within 10 mins of re turn of spontaneous circulation. Conclusions: High-dose epinephrine di d not improve 2-hr survival rate, 24 hr survival rate, or neurologic o utcome, High-dose epinephrine resulted in severe tachycardia and hyper tension immediately after resuscitation and in a higher mortality rate immediately after resuscitation.