These can lead to sudden cardiac arrest SCA in extreme cases, though not all arrhythmias lead to such a serious event. An AED will not bring someone back from a bad car accident or revive someone who has fallen from a building unless, in both of these situations, the person was still breathing before experiencing a sudden cardiac arrest episode.
The goal of an AED is to reset the heart when it gets caught in an arrhythmia. This is achieved by sending it electric shocks that will interrupt the chaotic rhythm. The interruption ideally causes the heart to go back to beating a normal pace and rhythm. If there is no beat, irregular or not, shocking the heart will not benefit the patient and the AED will not deliver one.
You now know that AEDs send electricity to the heart, which is known as defibrillation. But, where does this electricity in the heart reside and why does a heart rhythm become abnormal? The defibrillator stops fibrillation, the condition in which the heart is experiencing arrhythmias and erratic beating.
It does this by sending over joules of electricity through the heart. This is called electrical cardioversion. Electrical cardioversion is extremely effective during an emergency; however, it is only a temporary solution. The underlying condition that caused the arrhythmia will need to be treated to ensure the fibrillation does not return. In a healthy heart, a group of cardiac muscle cells known as the cardiac conduction system are responsible for sending an electrical signal to the heart.
These signals cause the heart to beat. The cardiac conduction system starts its work in the right atrium, which is an upper chamber, and the signal is sent down to the ventricles, which are the lower chambers. The signal sent through the heart by the cardiac conduction system causes the heart to contract in an organized rhythm.
This causes the body to become deprived of its normal blood supply, which is why the person experiencing an arrhythmia starts to feel faint. Arrhythmias can have many causes, including heart disease, stress, substance abuse, or scarring from prior heart attacks. Arrhythmias are dangerous because when your blood is not pumping properly, the result can be a heart attack, a stroke or even worse, sudden cardiac arrest. During defibrillation, the heart is stopped long enough to allow the contractions to reset.
The large pulses of energy released by the defibrillator come from a built-in battery. This energy is sent down the two wires attached to the device which are capped off by paddles.
One paddle should be located above and left of the heart or on the lower right of the heart. The second paddle should be placed in front of the heart, which would be on top from the perspective of the person placing the pads.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more.
Why is defibrillation in asystole "flat line" useless? Ask Question. Asked 7 years, 2 months ago. Active 1 year, 7 months ago. Viewed 54k times.
If anyone could please explain, that'd be great. Improve this question. March Ho 9, 3 3 gold badges 34 34 silver badges 72 72 bronze badges. Add a comment. Active Oldest Votes. Improve this answer.
Nzall Nzall 2 2 silver badges 6 6 bronze badges. While I cannot find an obvious reference for the "causes asystole" bit, I think that the calsprogram link might have it in a linked page. All this info was found in 5 minutes of googling. I really suggest you try doing this research yourself next time. It'll be faster that way. CPR merely provides a semblance of circulation mechanically while the heart is not doing so intrinsically due to whatever arrhythmia. This is known as cardiac arrest.
We can see the various electrical wave patterns of the heart in cardiac arrest using an electrocardiogram or ECG. There are four main rhythms you might see during a cardiac arrest:. Pulseless ventricular tachycardia and ventricular fibrillation 1 and 2 are shockable, largely because they tend to be caused by the electrical activity of the heart being thrown out of whack, and not by the heart muscle itself being badly damaged.
Hitting the heart muscle with a big dose of electrical energy acts a bit like hitting Ctrl-Alt-Delete on your computer or Alt-Command-Esc for the Mac users. A single shock will cause nearly half of cases to revert to a more normal rhythm with restoration of circulation if given within a few minutes of onset.
These rhythms indicate that the heart muscle itself is dysfunctional; it has stopped listening to the orders to contract. The causes are hard to reverse and survival rates are very low.
0コメント