The Chain of Survival sums up the sequence of events that needs to take place to prevent or treat an episode of SCA. This sequence is
	1. Health Check Make sure you visit your physician if you have one or more risk factors.
	2. Early access to emergency care First, you or other witnesses must recognise the emergency. You must recognise the warning signs of a heart attack, cardiac arrest, stroke, or choking. Anyone who is unresponsive should receive emergency care. As soon as an emergency is recognised, call the emergency number 999.
	3. Early Cardiac Pulmonary Resuscitation (CPR) CPR is the critical link that buys time between the first link (calling emergency care) and the third link (using the External Defibrillator). The earlier you give CPR to a person in cardiac or respiratory arrest, the greater their chance of survival. CPR keeps oxygenated blood flowing to the brain and heart until defibrillation or other advanced care can restore normal heart action.
	4. Early defibrillation The only effective way to treat sudden cardiac arrest (SCA) is with an electrical shock delivered by a defibrillator. Voltage stored by the defibrillator pushes electrical current through the heart by means of the electrodes or paddles placed on the chest. This brief pulse of current halts the chaotic activity of the heart, giving it a chance to start beating again with a normal rhythm. Delivering a shock that returns the heart to a normal rhythm is called defibrillation. The sooner you provide defibrillation with an Automatic External Defibrillator or a manual defibrillator, the better the victim's chances of survival. For every minute that a person in cardiac arrest must wait to be defibrillated, their chance of survival decreases by 10 per cent. After 10 minutes, the chance of survival is less than 10 per cent.
	5. Early advanced life support This link is provided by highly trained emergency medical personnel They give basic life support and defibrillation as well as more advanced care. They can give cardiac drugs and insert endotracheal breathing tubes. These advanced actions help the heart in VF respond to defibrillation or maintain a normal rhythm after successful defibrillation.
	6. Implantable therapy A previous episode of SCA often predicts another occurrence. Prevention is critical to survival. An Implantable cardioverter defibrillator (ICD) uses energy to stop life-threatening heart rhythms and return the heart to a normal rhythm.
Last Updated on: 20.01.2005