What problems can defibrillators fix, and why can’t we use them with all cases? Why is there, apparently, a time limit on their use for a patient?


What problems can defibrillators fix, and why can’t we use them with all cases? Why is there, apparently, a time limit on their use for a patient?

In: Biology

It can help with cardiac arrest, you can’t use them with all cases as some people have the pace maker. There is a time limit due to the stagnation of blood causing clots which can create another heart attack and or stroke.

Defibrillators do only one thing — jolt the heart muscles. But the muscles need structure, healthy cells and a healthy nervous system to continue functioning.

Think of a defibrillator like the starter motor in a car. The starter uses power from the battery to crank the pistons to get the engine going. Then the starter motor stops adding energy to the system, because the engine is going by itself, burning gasoline.

The starter can’t drive the pistons for very long before it burns out or drains the battery. The starter can’t make pistons fire if the pistons are damaged. The starter can’t run the engine without gasoline providing power. Etc, etc.

Defibrillation only fixes ventricular fibrillation or ventricular tachycardia. These are when the heart is beating irrationally and not taking signals from the internal pacing system. Defibrillation causes a burst of electric current that causes the heart cells to pause and allow the pacemaker to take over again.

It does NOT help when the heart has “flatlined” or has stopped beating.

The heart is several muscles working together, if they stop working together, no blood gets pumped.
All the muscles doing their own thing randomly and not pumping blood is called fibrillation.

So how do you fix it?


The defibrillator is the turning it off part.
It briefly shuts down everything in the heart, by overpowering every other signal.
Then you use stuff like CPR to hopefully turn it on again.
Hopefully rebooting the heart fixes the problem.

But not everything can be solved by a reboot, and often it just stop it from killing the patient then and there, but not fix the underlying problem, such as the thing that’s supposed to coordinating the heart not working.

Do note, if the heart is already stopped, turning it off does absolutely nothing. This is something sooooo many medical dramas get wrong.

As for the time limit, the heart not pumping due to fibrillation means blood isn’t flowing to the brain, so the brain dies. Also the heart it self needs blood too, so that dying as well is really bad.

Your heart muscles are themselves responsible for keeping their rhythm. And they keep in sync by sensing what the rest of the muscle is doing. However there are several conditions that may cause the muscles in the heart to come out of sync with each other. Once you have made sure the underlying cause have been fixed so that the condition does not happen again then you can use a defibrillator to give the heart muscles a jolt so that they all beat at the same time and comes back into rhythm again.

Not all heart problems will cause this condition though. For example if the heart stops there is no muscle contractions to get back in sync. But once you have fixed the cause of the stopped heart it will start up again and may not all start in rhythm so you may need to use a defibrillator then.

And defibrillators do not work unless you have fixed the issue that caused the situation in the first place. It is only used to fix a symptom and not what causes the symptom. So if you have used a defibrillator and the heart muscles is still not in sync then you have not cured the condition and you need to diagnose it and cure it before there is any reason to try the defibrillator again. Sometimes the body is able to cure the issue by its own and sometimes the drugs may take some time to take effect or you may need to give another dose. But it may also be an undiagnosed condition or that there are no cures for the severity the patient have.