Epidemiology and Treatment of Opioid-Related Cardiac Arrest

PHILADELPHIA — Individuals suffering cardiac arrest due to opioid overdose tend to be younger and have fewer chronic conditions, and may be more likely to receive cardiopulmonary resuscitation (CPR) from bystanders, according to research presented at the 2019 American Heart Association Scientific Sessions, held November 16 to 18 in Philadelphia, Pennsylvania. These patients may also be more likely to survive long enough to be admitted into emergency departments (EDs).¹

Opioid-related cardiac arrests (ORCAs) are increasing in frequency across a number of geographic regions in the United States. To improve prevention and treatment of ORCAs in Maine, the current study was designed to assess how the state’s rural and urban areas are affected by this public health threat. To test the hypothesis that significant variance in clinical features, demographics, rurality, and survival until ED admission is present between ORCA and non-ORCA patients, investigators analyzed data from the National Emergency Medical Services Information System between 2016 and 2017. The data included all 911 emergency responses in which emergency medical services (EMS) reported non-traumatic out-of-hospital cardiac arrest (OOHCA).

ORCA was defined as a primary etiology of EMS-suspected opioid overdose or overdose without established etiology and naloxone administration during CPR. Rural-Urban Commuting Area Codes were used to assign rurality. Arrest-specific factors and demographics were compared between ORCA patients and non-ORCA patients, followed by logistic regression to evaluate associations between ORCA and survival to ED admission.

Among 3131 EMS OOHCA responses, 5% (n=168) met the definition of ORCA. ORCA patients were younger (35±9 years vs 62±17 years; P <.001), less likely to have a chronic medical condition (P <.001-.02) or an initial shockable rhythm (12% vs 28%, P <.001), less likely to occur in a public place (13% vs 23%, P =.02) or be witnessed (38% vs 60%, P <.001), but were more likely to receive bystander CPR (27% vs 16%, P <.001) and to report illicit drug use (19% vs 2%, P <.001). ORCAs were more likely to occur in large rural or metropolitan areas compared with isolated rural or small rural areas (75% vs 25%, P <.001).

After adjusting for age, sex, initial shockable rhythm, bystander CPR, witnessed arrest, and rurality, patients with ORCA had increased odds of surviving until ED admission (odds ratio, 1.83; 95% CI, 1.11-2.95).

“Given what we found, it might be appropriate to consider thinking about these cardiac arrest cases differently and to raise awareness among first responders and emergency room providers that opioid-related cardiac arrests are in fact different from other cardiac arrest cases,” concluded study investigator Teresa May in a press release,² She goes on to say, “I believe patients who suffer a cardiac arrest due to opioid overdose should be recognized and studied as an entirely different type of cardiac patient. They may require different pre-hospital and in-hospital treatment than other patients with cardiac arrest.”

References

1. May T, Gagnon D, Seder DB, et al. Opioid-related cardiac arrest incidence and epidemiology in Maine.  Presented at: American Heart Association 2019 Scientific Sessions; November 16-18, 2019; Philadelphia, PA. Abstract 230.
2. Opioid-related cardiac arrest patients differ from other cardiac arrests [news release]. Dallas, TX: American Heart Association. Published November 11, 2019. https://newsroom.heart.org/news/opioid-related-cardiac-arrest-patients-differ-from-other-cardiac-arrests. Accessed November 13, 2019.