A statewide system in Arizona for directing out-of-hospital cardiac arrest patients to 31 designated cardiac receiving center (CRC) hospitals that provide guideline-based post-arrest care more than doubled risk-adjusted rates of both survival and survival with good neurologic status. The impact of this system, with the voluntary participation of 120 emergency medical services (EMS) agencies and covering 80 percent of the state’s population, was recently reported in Annals of Emergency Medicine.¹

“We believed lives would be saved if the hospitals implemented the guidelines for post-arrest care and if we were able to get arrest patients to those hospitals,” said lead author Daniel Spaite, MD, director of EMS Research Collaboration and endowed professor at The University of Arizona in Tucson. The project is a partnership between EMS agencies, hospitals, the Arizona Department of Health Services (ADHS), and The University of Arizona in which designated CRCs commit to 24-7 guideline-based provision of therapeutic hypothermia and coronary angiography and percutaneous coronary interventions (cath/PCI), along with a bundle of other interventions.

ADHS worked closely with hospitals on implementing the guidelines and becoming recognized as CRCs starting in 2007. Then the department established protocols directing EMS agencies to transport cardiac arrest patients to the designated centers. Researchers compared survival rates before and after systemwide intervention, with survival increasing by more than 60 percent by 2010 (with adjusted odds ratio of more than 2).

“Whether targeted temperature management aims for mild therapeutic hypothermia (32–34 degrees C) or ‘merely’ prevention of fever (36 degrees C), either way, the emergency physician has to gear up in the same way because post-arrest patients reliably have increased body temperature if that is not actively managed.”
–Daniel Spaite, MD, director of EMS Research and endowed professor at the University of Arizona in Tucson

The hospitals in this project followed current guidelines, which recommend mild therapeutic hypothermia. Recent studies have called into question the best target temperature for post-arrest patients. “While we ultimately cannot say for sure, it is very likely that therapeutic hypothermia was responsible for a significant part of the improved outcomes,” Dr. Spaite said. “Whether targeted temperature management aims for mild therapeutic hypothermia [32–34ºC] or ‘merely’ prevention of fever [36ºC], either way, the emergency physician has to gear up in the same way because post-arrest patients reliably have increased body temperature if that is not actively managed.”

Anticipated controversy from non-CRC hospitals that were bypassed in the protocol because they weren’t CRCs failed to materialize. “It helped that participation was voluntary and a hospital simply had to commit to providing 24-7 guideline-based care and sharing their data,” said co-author Ben Bobrow, MD, the state’s EMS medical director and professor of emergency medicine at The University of Arizona. The number of CRC-designated hospitals has since grown to 40 out of 62 facilities in the state, and small- to medium-sized hospitals have showed as much improvement in survival as large ones.

Safety concerns about bypassing hospitals were allayed by two studies conducted by the authors prior to implementation. The Save Hearts in Arizona Registry & Education (SHARE) database showed that there is no increase in the risk of death when patients spend longer in transport, a finding corroborated by the OPALS database.^2,3 The protocol in the current study directs EMS agencies to bypass a closer hospital so long as it increases transport interval by no more than 15 minutes.

This is the first study to look at the impact, across an entire state, of regionalization of coordinated out-of-hospital cardiac arrest treatment and transport, as endorsed by the American Heart Association in 2010, Dr. Spaite said.⁴ “It makes us optimistic that this voluntary model of implementation may be transportable to many other settings since it was successful across such a wide variety of EMS systems and receiving facilities.”

The prospective before-and-after study’s findings are consistent with the intent of regionalization and are associated with significant increases in both the number of patients arriving at CRC-designated hospitals and the use of guideline therapies, the Annals article notes. Provision of therapeutic hypothermia among patients who had return of spontaneous circulation increased from 0 percent to 44 percent, while provision of cardiac cath/PCI went from 11.7 percent to 30.7 percent.

The authors encourage emergency physicians to adapt this approach in their own hospitals, EMS systems, and communities. “If you are an emergency medicine leader in your hospital, there’s no reason why you can’t work with other hospitals and EMS leaders to implement this model in your own system,” Dr. Spaite said.

References

1. Spaite DW, Bobrow BJ, Stolz U, et al. Statewide regionalization of postarrest care for out-of-hospital cardiac arrest: association with survival and neurologic outcome. Ann Emerg Med. 2014 Jul 23. pii: S0196-0644(14)00487-9. Spaite DW, Bobrow BJ, Vadedoboncoeur TF, et al.
2. The impact of prehospital transport interval on survival in out-of-hospital cardiac arrest: implications for regionalization of post-resuscitation care. Resuscitation. 2008;79:61-66.
3. Spaite DW, Stiell IG, Bobrow BJ, et al. Effect of transport interval on out-of-hospital cardiac arrest survival in the OPALS study: implications for triaging patients to specialized cardiac arrest centers. Ann Emerg Med. 2009;54:248-255.
4. Nichol G, Aufderheide TP, Eigel B, et al. American Heart Association policy statement: Regional systems of care for out-of-hospital cardiac arrest. Circulation. 2010;121:709-729.

Mr. Beresford is a freelance journalist based in California.