Out of hospital cardiac arrest

Out of hospital cardiac arrest

Out of hospital cardiac arrest is an important mechanism of death throughout the world and the survival rates are poor even in those who are resuscitated.¹ Survival to discharge range from two percent in Asia to eleven percent in Australia, with Europe and North America coming in between.
It is well known that the critical links in the chain of survival for out of hospital cardiac arrest (or for any cardiac arrest for that matter) are early activation of emergency response, early cardiopulmonary resuscitation (CPR), early defibrillation, advanced life support and post resuscitation care. Like any other chain, this chain is also as strong as its weakest link in the given scenario of cardiac arrest.
Early initiation of good quality CPR is one of the important determinants of survival. But CPR alone may not do much but to buy time unless the next links in the chain are readily available because of the limited time window for which a meaningful recovery is possible, without the other links following in sequence. All the same, this does not negate the value of early CPR which is indeed the most important initial step.
Wider access to public access defibrillation with automatic external defibrillators (AED) will go a long way in establishing earlier return of spontaneous circulation (ROSC). A good emergency response team and easy access with good transport system to a well equipped centre is equally important in attaining return to a useful life after resuscitation. Therapeutic hypothermia is increasingly being used for cerebral protection after successful resuscitation. Further advanced therapies like percutaneous coronary intervention in cases of acute myocardial infarction causing out of hospital cardiac arrest are also gaining importance.

Reference

1. Berdowski J et al. Global incidences of out-of-hospital cardiac arrest and survival rates: systematic review of 67 prospective studies. Resuscitation,2010: 81:1479-1487.