What Is a Heart Defibrillator?

An important 20th century development in the medical field was the creation and advancement of the heart defibrillator. This device utilizes electric charges to shock the heart and establish a normal heartbeat. The heart defibrillator is used when the heart muscles are contracting abnormally, which obstructs blood flow. This device can jolt the heart muscle to correct its behavior and re-establish blood flow.

History

• The technology and procedure for heart defibrillation was first demonstrated in 1899 by two Swiss physiologists who discovered that electrical pulses could reverse abnormal heart rhythm in dogs. In 1947, this technology was used on a human during open heart surgery. At that time, paddles that conducted electricity needed to be directly applied to the heart. In the 1950s, it was discovered that by using charges of more than 1,000 volts, regular heart rhythm could be restored without opening the chest cavity. In the 1960s, portable defibrillators were introduced.

Function

• A heart defibrillator is used to restore the heart's normal rhythm during cardiac arrhythmia, such as fibrillation or ventricular tachycardia. During fibrillation, the heart contractions of the heart ventricles are sporadic and unable to properly pump blood. During ventricular tachycardia, the ventricles work too fast and can result in no pulse. Electricity from the defibrillator is used to restore a normal heart beat. The defibrillator takes about 30 seconds to gain an electrical charge and then the paddles administer the charge through paddles placed on the chest.

Types

• External defibrillators can be manually or automatically operated. External defibrillators must be used by trained medical professionals as it is up to the operator to determine the amount of electricity to be administered. Automatic external defibrillators can read cardio activity and determine what electrical treatment is necessary. Semi-automatic external defibrillators have a built-in heart monitor as well as a manual override option. Implantable defibrillators are also available. These devices constantly monitor the heart rate and administer shocks as necessary.

Benefits

• A defibrillator is able to restore normal heart rate and, in many cases, prolong the life of the patient. Because of these devices, cardiac arrest does not necessarily result in death. Implantable defibrillators are able to quickly re-establish normal heart rate so that the patient does not need to wait for medical help. Automated external defibrillators also allow for quick treatment by a non-licensed person since the device automatically determines what treatment is necessary. Speedy treatment is essential during cardiac arrest, since the patient may only survive for minutes in such a condition.

Misconceptions

• There are several misconceptions regarding defibrillators, most of which are perpetrated through movies and television. For example, many movies or television shows portray a cardiac arrest patient as convulsing or jerking upwards violently after defibrillation. In reality, patients treated with a defibrillator may twitch slightly but generally do not move. Defibrillators are also shown to re-establish a pulse in a patient who has flat-lined. Defibrillators are not actually used to create a heartbeat in patients who have flat-lined.