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What Does An AED (Automated External Defibrillator) Do?

Using an Automated External Defibrillator can save the life of someone experiencing a heart attack or sudden cardiac arrest

(An earlier version of this article misspoke about what defibrillators can do for cardiac arrest, as well as the definition of fibrillate. Below is an updated version with sources and corrected information.)

The Oxford Living Dictionary defines the word “fibrillate” as: (of a muscle, especially in the heart) make a quivering movement due to uncoordinated contraction of the individual fibrils.”

The Circulatory System

A person’s heart runs their circulatory system: it pumps blood in and out.  The heart is controlled by an electrical system that tells the heart when to pump, and regulates the rhythm.  There’s much more to it (check out some of the sources below if you’re interested), but when a person’s heart arrests, or when it starts to quiver and beat irregularly, you need to use an AED (an automated external defibrillator).

Manual defibrillators, used by skilled medical professionals, are what are most seen on TV. They have paddles. You’ve probably heard an actor on a medical TV show yell, “Clear,” and shock someone. An AED, which are in many public places,  has patches instead.

Cardiac Arrest

The patches use just enough voltage to shock the heart back into a regular rhythm without burning the skin. It’s kind of like restarting a computer when it freezes up. The defibrillator tries to do just what its name says, it de-fibrillates, meaning that it stops the irregular beating and resets the heart to beat regularly.

There are many different heart health issues which can cause a heart to irregularly beat, but the most frequent occurrence is a heart attack.

When someone experiences cardiac arrest, it means their heart has stopped beating. A person who is experiencing cardiac arrest collapses, they aren’t breathing, they don’t have a pulse, and they aren’t conscious.

First Aid Skills

An AED when used correctly and within a few minutes of the person’s collapse, can increase their chances of survival. The AED when applied to a person will monitor their heart rate, calculate the right shock to help the person’s heart, and prompt whoever is using to push a button to allow the shock to be administered.

It’s highly encouraged for people to take classes in how to use an AED, as well as how to give CPR and chest compressions. The more people with professionally taught first aid skills, who can help those in, in case of an emergency the better.

Sources And Further Reading:

  • misscatherinemciver

    Dear sir/madam, I am writing to you with regards to my fiance, he suffered a heart attack, and lost oxygen for 8 minutes. Since then he has lost his sense of balance, but is suffering with quite a degree of memory loss. Could you please help me to help him.

    Kindest Regards

    Miss Catherine McIver

  • misscatherinemciver

    Dear sir/madam, I am writing to you with regards to my fiance, he suffered a heart attack, and lost oxygen for 8 minutes. Since then he has lost his sense of balance, but is suffering with quite a degree of memory loss. Could you please help me to help him.

    Kindest Regards

    Miss Catherine McIver

  • http://www.youareanidiot.org/ My Dixie Wrecked

    I”d be happy to help.

  • mragjr

    Based on the last sentence,”It [the defibrillator] can only help stop a heart attack. ” I am assuming the writer has no clue what they are talking about. Sudden Cardiac Arrest (SCA) and more specifically its cause, ventricular fibrillation can use a defibrillator to put the heart back into a normal rhythm. A heart attack is a blocked cardiac artery. One is electrical, the other plumbing. My understanding is a defibrillator (shock) actually first STOPS the heart and then allows it to “reboot.” Whatever the case, I’d suggest a further search.

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