In the 1970’s it was discovered in the medical profession that if a number of events were to take place in a particular order then a patient suffering from a heart attack stood a greater chance of survival. This process is now known as the....


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When a patient is suffering from cardiac arrest then an urgent 999 call is paramount. By making this one gesture a bystander can help save someone’s life. Could you recognise the symptoms of cardiac arrest?

Lack of consciousness
Lack of pulse
Cessation of breathing


CPR or Cardiopulmonary Resuscitation is the second link in the Chain of Survival; it is the link that can buy life-saving time between the first link (Early Access to Emergency Care) and the third link (Early Defibrillation)

During Sudden Cardiac Arrest, the heart twitches irregularly most often due to ventricular fibrillation (VF) and cannot pump oxygenated blood efficiently to the brain, lungs, and other organs. The victim quickly stops breathing and loses consciousness. However, prompt CPR can help sustain life during VF. The mouth-to-mouth breathing and chest compressions help oxygenated blood flow to the person’s brain and heart, until defibrillation can attempt to restore normal heart pumping.


Although it is an important link in the chain of survival, CPR alone cannot fully resuscitate a person in SCA. Early defibrillation is the third and perhaps most significant link. Most SCA (Sudden Cardiac Arrest) victims are in VF, an electrical malfunction of the heart that causes the heart to twitch irregularly. Defibrillation, the delivery of an electrical shock to the heart muscle, can restore normal heart function if it occurs within minutes of SCA onset.

When CPR and defibrillation are provided within eight minutes of an episode, a person’s chance of survival increases to 20%. When these steps are provided within four minutes and a paramedic arrives within eight minutes the likelihood of survival increases to over 40%.


The fourth link in the chain of survival is advanced care. Paramedics and other highly trained EMS personnel provide this care, which can include basic life support, defibrillation, administration of cardiac drugs, and the insertion of endotracheal breathing tubes. This type of advanced care can help the heart in VF to respond to defibrillation and maintain a normal rhythm after successful fibrillation. The trained EMS personnel monitor the patient closely on the way to hospital, where more definitive diagnostic evaluation can occur.