The electronic defibrillator is an essential medical instrument within the field of electrical defibrillation; this device generates electrical discharges that help restore the normal heartbeat of the patient suffering from arrhythmia.

This electromedical device, which can be battery-operated or plugged into a power outlet, generates electrical discharges via metal plates. Its use is commonly associated with resuscitation following cardiac arrest.

The purpose of the cardiac defibrillator is to deliver electrical shocks capable of restoring normal heart function in the event of a slowing of the heart muscle. Its life-saving function is essential in sporting activities.

An electric defibrillator is powered by a battery or plugged into an electrical outlet and delivers electrical discharges to a patient through two metal plates, also called electrodes. The two plates must be placed in different places:

• One under the right shoulder
• One under the left armpit
• One in the centre of the chest
• One on the back
• One under the right armpit

Thanks to these discharges, the heart muscles are awakened and the heartbeat regains its stability. In general, there are four types of electric defibrillators:

• The manual external defibrillator
• The semi-automatic external defibrillator
• The automatic external defibrillator
• The implantable cardiac defibrillator.

The manual external defibrillator works in conjunction with an electrocardiogram instrument, which can only be used under the guidance of a medical professional. The presence of the electrocardiogram helps to understand what type of electrical discharge to transmit to the patient. Operating it requires specific training, which is why it is only present in hospital settings.

The semi-automatic external defibrillator makes it possible to analyse an individual’s heartbeat and determine which electrical discharge to transmit. This analysis is done using the same metal plates that are used to transmit the discharge. These instruments are simple to use and require minimal training because they come with voice prompts to support the rescuer and tell them when to press the discharge button.

The automatic external defibrillator analyses the heartbeat, independently determines the electrical discharge to be transmitted to the patient, and releases it without the need for the rescuer to press any buttons. The user of this type of defibrillator only has to place the metal plates on the individual and let the device do its work. This device is usually found in public spaces.

The implantable cardiac defibrillator is very small, portable and capable of monitoring an individual’s heartbeat and delivering an electric shock to the heart at the most appropriate time. As a shape, it is very reminiscent of a pacemaker and requires surgery for its subcutaneous insertion. Once installed and on the basis of the patient’s heart condition, the doctor programs it with the use of an external device.

One of the most important precautions to take when using a defibrillator is to maintain a proper distance from the patient at the moment when the button for the electrical discharge is pressed, because if someone touches the patient when it is activated, they may receive part of the discharge, developing a more or less severe arrhythmia. In addition, if a patient with an implantable cardioverter-defibrillator gets shocked by a defibrillator, it could cause their cardioverter-defibrillator to malfunction and create unnecessary electric shocks.