A defibrillator is a tool which can assist in a human’s heart when ventricular fibrillation occurs. A defibrillator is a tool which saves lives.
Fibrillation occurs when many different cells begin to act as the pacemaker cells in the heart. It means that the heart is instructed to beat by many thousands of cells, all at different times and without rhythm. Such confusion leaves the heart incapable of pumping blood around the body. It causes death and cardiac arrest.
A defibrillator sends a high energy pulse to the bottom-middle of the heart from the top-right of the heart. It triggers all of the movement to interrupt the whole back. The usual pacemaker in the heart can then try and start regular beating again. Defibrillation aren’t always effective.
External defibrillator types
Implantable cardioverter-defibrillators (ICD) are defibrillators which are designed to help patients from within their bodies. These are put inside people who are at high risk of going into cardiac arrest and monitor the heart rate, rhythm and waveform of a person. Through measuring the activity in the multiple heart chambers an icd will identify and treat cardiac arrhythmias rapidly.
Often used in hospitals and ambulances are external defibrillators. These are now also being used more outside of medical settings as automatic external defibrillators are safer and cheaper (see below). There are many different types of external defibrillators, and advancement in cardiac science has led to major changes in the technology that underlies them.
Until the 1990s, external defibrillators relied on shock waves that were monophasic (one phase). Electrical pulses are rapidly sent in one direction from one electrode to another.
Nevertheless, biphasic defibrillation (two phases), switches the course of the pulses. It completes one cycle in about 10 milliseconds. This means less energy is needed to make defibrillation effective. That means less risk for burns and other injury. The small size of the condenser (battery) needed for the defibrillator will result in large cost and size reductions.
Automatic external defibrillators
An automatic external defibrillator with public access in Monaco. By the bystanders can use these.
The automatic external defibrillator (AED) is a self-contained device designed to be mobile, and simple to use. These are often shaped like briefcases, so that a handle can hold them. An AED comprises a battery, a controller, and electrodes. When the electrodes are placed on the patient, the patient will be measured by the control machine, monitoring their heart rhythm. It will then charge itself up to a reasonable level of power and tell users that the person needs to be shocked. If the patient does not need to be defibrillated, the automatic external defibrillator will not allow for the administration of a shock. To cause the shock, a button must still be pressed manually, as the operator must be certain beforehand that no one contacts the patient. Automated external defibrillators will often have speakers which will give instructions when opened.
Current portable external defibrillator devices are designed with limited medical knowledge for emergency medical technicians, home users, police and security personnel, and other individuals. Such machines are typically found in large places of meeting, such as airports, casinos, sports stadiums, and campuses.
The electrode is the part that gives off the shock from the defibrillator.
Traditional metal paddle with an insulated handle is the most popular type of electrode. This form must be kept in place on the patient’s skin when administering shocks. Gel must be added to the patient’s skin before the paddles are used so that there is a good connection and electrical resistance is minimised.
One type of resuscitation electrode is built as an adhesive pad that can be pinned to a patient’s skin. Such electrodes are left with a defibrillator connection. If defibrillation is required, the system will be charged and the shock will be administered, without having to apply any gel or remove any paddles and position them.
There are two adhesive electrodes, both solid-and wet-gel. Solid-gel electrodes are more comfortable, since after removing the electrodes, there is no need to clean the patient’s face. Nonetheless, the use of solid-gel electrodes during defibrillation poses a higher risk of burns, as wet-gel electrodes conduct electricity more uniformly into the body.
Defibrillators are often portrayed in popular cultural representations in films, television, video games, and other fictional media. This is because it is able to bring about dramatic improvements in patient health rapidly. But their role is often over-exaggerated.
Medical providers are often shown to defibrillate patients with an ECG “flat-line” rhythm (also known as asystole); this is not achieved in real life, as the defibrillator itself does not restart the heart.