Abstract 258: Coronary Perfusion Pressure Response to Administration of Intraosseous Epinephrine After Prolonged Cardiac Arrest
Background: While provision of vasopressors during attempted resuscitation of OHCA victims has never been shown to improve neurologically intact survival, its short-term benefits are clear. Despite evidence that the IO dose should be substantially higher than that given IV to achieve pharmacokinetic and hemodynamic equivalency, current guidelines still recommend a dose of 0.01 mg/kg regardless of delivery route (IO or IV).
Objective: To compare the effect of epinephrine 0.1 mg/kg (HDE) IO with 0.01 mg/kg (SDE) IV on coronary perfusion pressure (CPP) during resuscitation in a swine model of prolonged VF.
Methods: This was a secondary analysis of prospectively collected data from two IACUC approved protocols. Seventy-nine Yorkshire swine (25-30 kg) were surgically instrumented under anesthesia and VF was electrically induced. After 10 minutes of untreated VF in the IO study (n=26) and 12 minutes of untreated VF in the IV study (n=53), resuscitation commenced with precordial chest compressions. After 30 seconds of initial chest compressions, a single dose of epinephrine (HDE IO or SDE IV, respectively) was given followed by a large volume saline flush. An additional 2.5 minutes of compressions were provided after injection to circulate the medication before the first rescue shock (RS) was delivered. CPR and RS attempts were standardized for all animals. The CPP was defined as aortic diastolic pressure minus right atrial diastolic pressure and the values were extracted immediately following the last compression before defibrillation for the first RS in each animal. Descriptive statistics were used to analyze the data.
Results: After 10 minutes of untreated VF, HDE IO epinephrine resulted in a mean CPP of 33.2 mmHg (95%CI: 26.6, 39.9) just prior to RS1. After 12 minutes of untreated VF, SDE IV epinephrine resulted in a mean CPP of 25.0 mmHg (95%CI: 20.5, 29.4) just prior to RS1.
Conclusion: This observation study reaffirms the assertion that HDE may be required to generate CPP values similar to SDE delivered IV during resuscitation of prolonged VF. A randomized comparison of HDE and SDE IO in the metabolic phase of VF is needed to test this hypothesis and to determine the impact on ROSC and short-term survival.
- © 2012 by American Heart Association, Inc.