Outcomes of Out-of-Hospital Cardiac Arrest Patients Who Received Naloxone in an Emergency Medical Services System With a High Prevalence Of Opioid Overdose

Opioid-associated out-of-hospital cardiac arrest (OA-OHCA) is a subset of cardiac arrests that could benefit from measures outside of standard Advanced Cardiac Life Support (ACLS), such as naloxone.

In this study, we sought to examine whether OHCA patients chosen for naloxone therapy by emergency medical services (EMS) clinicians in a system with high rates of opioid overdose would have increased rates of return of spontaneous circulation (ROSC) and survival to hospital discharge.

The study took place in an urban EMS system with a high prevalence of opioid overdose. Paramedics could administer naloxone in cardiac arrest in addition to ACLS. It was often administered based on clinical gestalt for suspected OA-OHCA. The outcomes of OHCA patients who received naloxone were compared against those who received usual care in both an adjusted and unadjusted fashion. Lastly, we created a logistic regression model to test for an independent association of naloxone administration on ROSC and survival to hospital discharge.

A consecutive sample of 769 OHCA patients was obtained, of which 175 (23%) received naloxone. On average, patients who received naloxone had significantly fewer comorbidities and were younger. There was no difference in ROSC, survival to hospital discharge, or modified Rankin Scores. Using logistic regression modeling, there was no statistically significant effect of naloxone administration on these outcomes.

OHCA patients who received naloxone, despite being younger and having fewer comorbidities, had similar outcomes compared to those who received usual care. The difference in baseline characteristics suggests that paramedic gestalt reasonably selected for OA-OHCA.