Automated External Defibrillators & The Chain Of Survival

Automated External Defibrillators AED

MyMedEquip Admin |

Simply put, the heart maintains circulation. We all know that without circulation life can’t be sustained.

Sudden Cardiac Arrest (SCA) strikes without warning and gives little time to react. The condition is triggered by an electrical malfunction in the heart which causes it to stop beating. Blood stops flowing to the brain, lungs and other vital organs. Without treatment, it is usually fatal within minutes. SCA can affect people of any age who appear perfectly healthy and have no known heart disease or other risk factors. That makes it critical to be prepared to significantly increase the chances of survival.


What is a defibrillator?

The heart depends upon organised electrical activity to contract its various chambers in a coordinated fashion and produce blood flow throughout the body.

Various pathologies can cause the heart’s normal electrical activity to become disorganised (ie ventricular fibrillation). These include congenital defects, electrolyte disturbances, drug intoxication and, of course, acute myocardial infarction. Each of these can result in a decrease or cessation of blood flow.

Many years ago, there was a breakthrough in medical science when the defibrillator was invented. But these original devices required the intervention of a clinician.

Then Automated External Defibrillators (AEDs) were invented. AEDs brought clinical empowerment into the hands of the lay rescuer – what a breakthrough that was!

AEDs are devices designed to interrupt disorganised electrical activity in a person’s heart, allowing the conduction of the SA Node to coordinate cardiac electrical activity once again.

However, AEDs are not the sole determining factor in an effective resuscitation. In the case of SCA, good Cardiopulmonary Resuscitation (CPR) is essential to oxygenate the brain and other important organs.


The Chain of Survival is the unanimously accepted approach to resuscitation. It states the following:

Chain of Survival

  1. Early Access (i.e. someone has to get to the person quickly and call 000)
  2. Early CPR (i.e. someone must perform effective CPR quickly)
  3. Early Defibrillation (i.e. apply an AED)
  4. Early Advanced care (i.e. get the victim into advanced medical care quickly)

 restart a heart chance of survival SCA

About 70% of all bystander CPR is ineffectively performed and this includes both lay and trained rescuers. This is because the rescuer has no way to make clinical determinations as to whether their compressions are actually effective. To make matters worse, there is a huge differential of force required from victim to victim depending on their build. We can’t impart all of this during training because it introduces complexity, and simplicity is the key – any attempt at CPR is better than no attempt, we are taught.

AED cardiac arrest survivability

Clinical feedback during CPR, not retrospective feedback, is the solution

We’ve carefully selected our range of AEDs to include the best in the market. Our partners HeartSine Technologies spent years looking for the answer to poor CPR – and found it. The Samaritan 500P takes clinical readings during CPR, (as opposed to other AEDs that at best give feedback using superficial factors during CPR – i.e. how hard you’re pushing) and provides the rescuer with feedback based on cardiac output and other clinical factors. So now your clients can be sure to make the weak link in the chain a strong one and save more lives!

There are people alive today that have been saved by the HeartSine and LIFEPAK AEDs we stock… and others who have the comforting knowledge that they did everything they could.

Investing in an AED is a great step forward because it can increase the chance of survival for witnessed Cardiac Arrest from 5% to 85% – when combined with the other links in the chain of survival.

 HeartSine Samaratin 500P AED

MyMedEquip is a prominent distributor of HeartSine Defibrillators in Australia including the full HeartSine Samaritan PAD AED range.