How Does an AED Work?

Automated external defibrillators, more commonly known as AEDs, are portable devices which are used in order to diagnose cardiac arrhythmias and ventricular tachycardia. These conditions are both potentially fatal if not immediately recognized and treatment for them sought. Not only are automated external defibrillators able to detect the presence of these life threatening situations, they are also able to treat arrhythmias and tachycardia by using electricity to bring the heart back to a regular, healthy beat. Arrhythmias do not mean a cessation of the heart’s function, but instead cause an unhealthy, life threatening rhythm. In the case of ventricular tachycardia, the heart beats at a beat too rapid for the pumping of blood to be effective. If tachycardia is not treated, the heart could eventually reach asystole in which there is no cardiac contraction meaning that all electrical activity of the heart has ceased. At the point where asystole is reached, the survival of the patient is in extreme danger. The only way for a positive outcome to be reached, a successful combination of drugs which promote cardiac stimulation as well as CPR is required. If these treatments are not sought in a timely fashion, the result will inevitably be brain damage and eventual death. Brain damage occurs quickly after the heart has stopped. Because the brain requires a constant supply of blood, the cessation of blood flow to the brain swiftly leads to permanent injury to the brain. Typically, irreparable damage to the brain will occur after about three to four minutes of asystole. The AED is such a useful and necessary asset because, unlike internal defibrillators which need to be surgically inserted into the patient, they are external meaning that they can be used quickly and by any layman. Automated external defibrillators operate through the placement of electrodes on the patient’s chest. After external placement on the patient, the AED is able to determine the condition of the individual in order to determine whether the patient is experiencing cardiac arrhythmia. The AED uses both visual and well as voice prompting in order to make the condition of the patient apparent to the rescuer. If an irregularity is found, automated external defibrillators will tell the person operating the device whether or not CPR should be performed. If, instead, the device determines that the patient requires an electric shock in order to treat the current condition, the device will instruct the rescuer to step back from the patient so that a shock via an electric current can be administered through the electrodes that were placed on the chest of the individual. If an electric shock is given through the automated external defibrillator, the cardiac activity of the heart will be temporarily stilled. The theory is that the complete halt of electrical activity in the heart will allow the cardiac rhythm to be restarted, hopefully this time with a healthy and strong beat. AEDs are a necessary addition to any home or business establishment because of their efficiency and usability. Unlike other heart treatment devices, automated external defibrillators are able to be used by anyone instead of exclusively those with medical training. Because of this, these devices could potentially save the life of those at risk for cardiac arrest before the arrival of the ambulance or the emergency medical technician.