Research - Resuscitation
Sudden cardiac death is a major public health issue in the United States and around the world. An estimated 295,000 out-of-hospital cardiac arrest (OHCA) patients are evaluated by Emergency Medical Services (EMS) every year in the U.S. Despite advances in technology and resuscitation techniques, the outcome for cardiac arrest patients is still poor and varies among cities and regions.
For those patients who regain a pulse after cardiac arrest, morbidity and mortality remains high due to secondary brain injury. For all adult patients having a cardiac arrest in the out-of-hospital setting, with any first recorded heart rhythm, approximately 7.9 percent survive to hospital discharge. Many patients never regain consciousness and die as a result of anoxic brain injury rather than from their initial cardiac insult.
The CRU, in partnership with Wake County EMS, studied 1,365 adult patients treated for cardiac arrest by emergency responders. The observational time series ( January 2004 through October 2007) measured survival to hospital discharge in patients with out-of-hospital cardiac arrest during a tiered implementation of the 2005 American Heart Association (AHA) guidelines for compressions, ventilations and induced hypothermia.
The sequential addition of updated protocols for minimally interrupted chest compression, strict avoidance of hyperventilation and postresuscitation hypothermia therapy more than doubled the overall survival to hospital discharge rate for all attempted resuscitations (4.2 percent to 11.5 percent), representing an additional 25 lives saved annually within Wake County. Additionally, this study was named one of the top five Research Advances in 2010 from the American Heart Association's Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation.
COMMUNITY PARTNER: Wake County EMS
The Wake County Emergency Medical Services (EMS) system responded to 80,861 requests for service in 2011 and 84,867 in 2012. Among the system’s major achievements have been a nationally recognized cardiac arrest save rate, implementation of a pioneering ICE (induced hypothermia by EMS) protocol for cardiac arrest patients, and system-wide closest-vehicle dispatching using GPS-based automatic vehicle location and the MARVLIS in-vehicle navigation system. Wake County EMS has several specialized teams, including Hazardous Materials Medical Emergency Response with USAR paramedics trained and equipped to provide specialized care to victims of hazardous materials events and technical rescue situations. Data and research are an integral part of the Wake EMS system, which makes Wake EMS a valuable research partner.
- Nationwide, the overall rate of “neurologically intact survival” for patients who suffer cardiac arrest is about 8 percent at best (in superior systems who report to CARES, a national cardiac arrest registry). In Wake County, that rate is 16 percent.
- For individuals who suffer a witnessed cardiac arrest and are found in a “shockable” cardiac rhythm, Wake EMS has a 45 percent survival rate for these patients, compared with a national average of superior systems of 32 percent.
- In 2012, 62 people survived an out-of-hospital cardiac arrest of cardiac etiology in Wake County and 59 of them (95 percent) survived “neurologically intact” with preserved brain function.