Optimal weight-based epinephrine dosing for patients with a low likelihood of survival following out-of-hospital cardiac arrest.

Abstract

Cardiac arrest patients presenting with non-shockable rhythms have a low probability of survival, and epinephrine is one of the few pharmaceutical options for this group. The recommended 1.0mg adult dose is extrapolated from early animal studies and lacks adjustment for patient weight. Although several prior studies have investigated "low-" and "high-" dose epinephrine, none have identified a benefit to either strategy. To identify an optimal weight-based epinephrine dose for return-of-spontaneous-circulation (ROSC) after a single bolus among patients with low likelihood of survival. Included were adult patients who experienced a witnessed, non-traumatic out-of-hospital cardiac arrest prior to EMS arrival. Patients with shockable presenting rhythms or receiving bystander CPR were excluded. The AUROC was used to assess the predictive value of epinephrine dose (mg/kg) for ROSC following a single bolus. From the ROC curve, the optimal threshold dosage (OTD) was determined using the Youden Index. A logistic regression model calculated the adjusted odds ratio of OTD on ROSC. A total of 2,463 patients met inclusion criteria, of which 190 (7.7%) attained ROSC after the first epinephrine administration. The dosage AUROC for ROSC was 0.603 (p < 0.01). As calculated by the Youden index, the OTD was 0.013mg/kg. Patients receiving ≥ OTD were more likely to attain ROSC after a single epinephrine bolus (OR = 2.25,p < 0.001). Among patients with a low likelihood of survival, the optimal dose of epinephrine for attaining ROSC with a single bolus of epinephrine was 0.013mg/kg. These findings should inspire further investigation into optimal dosing strategies for epinephrine.