Question: What is a defibrillator and how does it work?
Answer :A defibrillator is an electrical device that provides a shock to the heart when there is a life-threatening arrhythmia present. The arrhythmia that we worry about is called ventricular fibrillation. This is a very rapid erratic beating of the heart.
Multiple parts of pacemakers in the heart starts sort of beating erratically and the heart can’t rhythmically contract. And what the defibrillator does, it provides shock that basically shocks the heart to stop so that it can start rhythmically contracting again.
Cardiac arrest, or cardiopulmonary arrest, occurs when the heart stops beating for any reason. One reason can be the failure of the electrical system in the heart to conduct impulses along the correct path. Random impulses firing all over the heart will cause it to shiver uselessly, not producing a pulse.
When the AED shocks the heart it causes the heart to stop momentarily. While the heart pauses, the small piece of tissue responsible for the next impulse (the sinus node or sinoatrial node) should fire off the next heart beat.
One thing to remember about AED’s: they only work on two specific scenarios. Only those two issues will benefit from an AED, and that’s what the machine is set to recognize. It will not save every patient in cardiac arrest. Indeed, AED’s often don’t help the patients they shock.