Push Dose Epinephrine Use in the Management of Hypotension During Critical Care Transport

Introduction: Hypotension is a critical event during the transport of critically ill patients. Push dose vasopressor use, though widely adopted by anesthesiologists, has only recently found use in the field of emergency medicine and may have utility in the management of out-of-hospital hypotension. This study aimed to characterize the hemodynamic effects and adverse events that occur following push dose epinephrine (PDE) administration by critical care transport (CCT) providers to correct documented hypotension. Methods: We performed a retrospective observational study of patients transported by a regional critical care transport service and who received PDE during transport to correct documented hypotension. Per protocol, 10-20 µg of 1:100,000 epinephrine was given intravenously every 2 min until: (1) the systolic blood pressure (SBP) was at least 90 mmHg, or (2) the mean arterial pressure (MAP) was 65 mmHg or greater. All patients were over 18 years of age and were transported between January 1, 2015 and December 31, 2016. Primary outcomes of interest were the primary diagnoses associated with PDE use, hemodynamic outcomes of the intervention, and adverse events. Results: During the study period 100 doses of push dose epinephrine were given during the transport of 58 patients. Of these, 94 (94.0%) were found to be appropriately dosed and indicated per protocol. The most common diagnoses associated with PDE use were: post-cardiac arrest (n = 24), sepsis (n = 9), altered mental status (n = 7), and cardiogenic shock (n = 3). The median increase in MAP across all doses was 13.0 (5.0-34.0) mmHg, and the heart rate increase was 2.0 (-1.0-9.3) beats per minute. Hypotension was resolved in 55 of 94 instances (58.5%). A single episode of transient extreme hypertension occurred after one PDE dose and did not result in patient harm. Conclusions: Push dose epinephrine may be an effective method of temporarily resolving hypotension during the CCT of critically ill patients. In the cases where PDE was administered, there was close adherence to the established protocol and adverse events were found to be rare directly following PDE administration. Further research is needed to validate these findings, establish optimal dosing, and evaluate use in non-CCT prehospital settings.