Chain of survival
The chain of survival refers to a series of actions that, properly executed, reduce the mortality associated with sudden cardiac arrest. Like any chain, the chain of survival is only as strong as its weakest link. The four interdependent links in the chain of survival are early access, early CPR, early defibrillation, and early advanced cardiac life support.
The "chain of survival" metaphor was developed by Mary M. Newman in 1987. It was used as a slogan for the 1988 Conference on Citizen CPR, described in an article she wrote for the Journal of Emergency Medical Services in 1989, and promoted in an editorial she wrote for the first issue of Currents in Emergency Cardiac Care in 1990. The American Heart Association later adopted the concept and elaborated on it in its 1992 guidelines for cardiopulmonary resuscitation and emergency cardiac care, The International Liaison Committee on Resuscitation (ILCOR) echoed the concept in 1997. The links of the Chain of survival are described below.
Ideally, someone must recognize an impending cardiac arrest or otherwise witness the cardiac arrest and activate the EMS system as early as possible with an immediate call to the emergency services. Unfortunately, many persons experiencing symptoms (for example, angina) that may lead to a cardiac arrest ignore these warning symptoms or, recognizing these warning symptoms correctly, fail to activate the EMS system, preferring to contact relatives instead (e.g., the elderly often contact their adult offspring rather than contact emergency services).
To be most effective, bystanders should provide CPR immediately after a patient collapses. Properly performed CPR can keep the heart in a shockable rhythm for 10–12 minutes longer.
Most adults who can be saved from cardiac arrest are in ventricular fibrillation or pulseless ventricular tachycardia. Early defibrillation is the link in the chain most likely to improve survival. Public access defibrillation may be the key to improving survival rates in out-of-hospital cardiac arrest, but is of the greatest value when the other links in the chain do not fail.
Early advanced care
Early advanced cardiac life support by paramedics is another critical link in the chain of survival. In communities with survival rates > 20%, a minimum of two of the rescuers are trained to the advanced level.
- Cardiac arrest
- Cardiac Arrest Registry to Enhance Survival
- Cardiopulmonary resuscitation
- "Part 12: From Science to Survival - Strengthening the Chain of Survival in Every Community," Circulation 2000;102:I-358
- Bossaert LL (1997). "Fibrillation and defibrillation of the heart". British Journal of Anaesthesia. 79 (2): 203–13. doi:10.1093/bja/79.2.203. PMID 9349131.
- Newman M (1989). "The chain of survival concept takes hold". JEMS. 14: 11–13.
- Newman MM (1990). "The Chain of Survival: Converting a Nation". Currents in Emergency Cardiac Care. 1 (1): 3.
- Cummins RO, Ornato JP, Thies WH, Pepe PE (1991). "Improving survival from sudden cardiac arrest: the "chain of survival" concept. A statement for health professionals from the Advanced Cardiac Life Support Subcommittee and the Emergency Cardiac Care Committee, American Heart Association". Circulation. 83 (5): 1832–47. doi:10.1161/01.cir.83.5.1832. PMID 2022039.
- "Guidelines for cardiopulmonary resuscitation and emergency cardiac care. Emergency Cardiac Care Committee and Subcommittees, American Heart Association. Part I. Introduction". JAMA. 268 (16): 2171–83. 1992. doi:10.1001/jama.268.16.2171. PMID 1404767.