Thirty years ago, it was discovered that if a series of events took place, in a set sequence, a patient suffering from a heart attack stood a greater chance of survival. These events are now known as the 'Chain of Survival'.
The First Link
When Sudden Cardiac Arrest strikes, an immediate 999 call is crucial; a delay of just a few minutes could prove fatal. By quickly recognizing a medical emergency, a bystander can help save a life.
Could you recognize the symptoms of Sudden Cardiac Arrest ?
Loss of consciousness
Lack of pulse
Cessation of breathing
Sudden Cardiac Arrest is not the same as a heart attack. However, a victim of either condition requires an immediate 999 call.
The Second Link
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.
The Third Link
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 victims are in ventricular fibrillation (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
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 respond to defibrillation and maintain a normal rhythm after successful defibrillation.
The trained EMS personnel monitor the patient closely on the way to the hospital, where more definitive diagnostic evaluation can occur.
Since more than 70% of sudden cardiac arrest cases occur out of hospital, it is unlikely that Paramedics will be on the scene at the onset. Community First Responders with quick access to defibrillators can be a vital asset when sudden cardiac arrest strikes.
People who survive sudden cardiac arrest have an excellent prognosis:
- 83% survive for at least one year, and;
- 57% survive for five years or longer.
This shows the important role that the First Responder plays in the Chain of Survival,bridging the time span between the 999 call and the arrival of the paramedic ambulance. Creating early access and therefore enhancing the chance of saving life.
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