Medical devices that give an electric shock to the heart, which are thought to be used during cardiac arrest due to movie scenes, are called defibrillators. Most of the scenes in the movies do not reflect reality. Contrary to popular belief, defibrillators are not used after the heart has stopped. In fact, the high electric current stops the heart, which is working irregularly or very close to stopping, for a very short time. Thus, it allows the heart to return to its old working mechanism. Defibrillators are used to prevent a troubled heart from stopping completely after a while. After the heart has stopped, the use of a defibrillator is useless, instead medication and CPR are required. Shocking the heart with a defibrillator stops the heart for a very short time. If the defibrillation application worked, the nerve cells that reach the stopped heart from the brain immediately continue to give new signals, and thus the heart continues to work as before. This app is like resetting the heart. There are different types of defibrillators in terms of working principles and functions. Although the usage patterns of the devices are similar to each other, there are some differences. What is an External Defibrillator? What is an Internal Defibrillator? What is a Monophasic Defibrillator? What is a Biphasic Defibrillator? What is a Manual Defibrillator? What is Automated External Defibrillator?
Fibrillation is the name given to the rapid and irregular beating of the lower or upper chambers of the heart. It can be expressed as the tremor of the heart chambers. It is a common rhythm disorder. The irregular functioning of the upper parts of the heart causes the lower parts of the heart to work irregularly. This confusion creates a problem in pumping the blood needed by the whole body, primarily the brain. It can be fatal if left uncorrected. Defibrillation (de-fibrillation) refers to the prevention of fibrillation with electrical current. During defibrillation, an electrical current is delivered to the heart. In this way, the irregular vibrations in the heart muscles are eliminated and the heart is aimed to work normally.
Almost all units of hospitals have defibrillators. It is kept ready for emergencies not only in hospitals, but also in family health centers, infirmaries, shopping centers, entertainment venues, airplanes and many public places. It is also available in ambulances. The devices are battery powered and can be used even when there is no electricity. It is a device that should be used by specialist healthcare personnel. Shocking should be done with settings appropriate to the patient's current needs. The success rate of defibrillation depends on how early it is done when needed. Every 1 minute of delay reduces the chance of experiencing it by approximately 8-12%. Some defibrillators also have options such as monitor, pacemaker, ECG, pulse oximetry and carbon monoxide measurement. Almost all of the devices on the market have the feature of recording all the events and parameters in the application process in their internal memory.
What are the Defibrillator Types?
The use of defibrillators ranks third in the basic life-saving chain. The most important of the procedures that can be done in emergency cases, which ensures the survival of the patients, is to inform the health teams and then to start CPR applications. If CPR is insufficient As a third procedure, electroshock can be applied with a defibrillator. There are several types of defibrillators, depending on how closely they are applied to the heart, how the electrical current is delivered, and how they work.
What is an External Defibrillator?
Devices that deliver electrical shocks through electrodes placed on the thorax without entering the body (non-invasively) are called external defibrillators. It is used by adjusting the high energy level, as electric current is given to the heart from distant points.
What is an Internal Defibrillator?
Devices that are applied by entering the body rather than outside the body and placing the electrodes directly on the heart or very close to the heart are called internal defibrillators. Since the electric shock is delivered directly to the heart or very close to the heart, the electrical energy given is compared to other defibrillators. quite a few amount. There are models that can be used during surgery, as well as models that can be used by placing on the body (pacemaker).
What is a Monophasic Defibrillator?
In monophasic (single pulse) defibrillators, the electric current flows in one direction. Electricity moves from one electrode to the other. An electric shock is applied to the heart between the electrodes once. Therefore, the energy level must be high (360 joules). The high energy level can also cause burns to the patient's skin and damage to the heart muscle (myocardial) tissue. Monophasic defibrillators have a 60% success rate in the first shock.
What is a Biphasic Defibrillator?
In biphasic (double pulse) defibrillators, the shock wave travels between the electrodes in two directions, positive and negative. Whichever direction the first current is conducting, the second current is conducted in the opposite direction. The electric current supplied to the chest wall moves in the positive direction for a certain period of time and then turns in the negative direction. To the heart between the electrodes two consecutive electric shocks is applied. A lower energy level (between 120-200 joules) can be used in biphasic defibrillators. This prevents side effects such as burns. In addition, the damage to the heart muscle (myocardium) tissue is less. Its double-pulse operation enables biphasic defibrillators to achieve 90% success in the first shock. Biphasic devices provide more successful results with less energy than monophasic devices.
What is an Implantable Cardioverter Defibrillator?
Defibrillator devices placed under the skin with a surgical procedure, that is, mounted inside the body, are called implantable cardioverter defibrillator (ICD). Their other name is is a pacemaker. An electrode coming out of the device, traveling through the upper main vein, reaches the heart. When the heart experiences problems such as ventricular fibrillation or pulseless ventricular tachycardia, the device automatically activates and gives an electric shock. Since it is transmitted directly to the heart, the electrical energy given is very small compared to other defibrillators.
What is a Manual Defibrillator?
The energy level to be applied in manual defibrillators is determined by the expert rescuer, taking into account the current needs of the patient. Apart from this, procedures such as seeing the rhythm, recognizing the rhythm, deciding on the appropriate treatment, providing safe defibrillation conditions and shocking are determined by the rescuer and applied manually.
What is an Automatic External Defibrillator?
There are 2 types of automatic external defibrillator (OED), semi-automatic and fully automatic. These devices are also known as AED (automated external defibrillator) in the market. AEDs work automatically with the software included in them. It determines the energy level needed by measuring the heart rhythm of the patient and applies it to the patient. It is non-invasive as it is applied externally. Automated defibrillators today form part of the life-saving chain. In fully automatic ones, the whole process is controlled by the device. These devices can automatically analyze the rhythm, decide whether the shock is necessary, manage the process with audible and visual warnings, charge the necessary energy and shock. In semi-automatic ones, the process up to the shocking moment is controlled by the device, only the shocking moment is applied by the expert rescuer. Fully automatic AEDs for the early intervention of non-physicians developed.
What are the Applications that Cause Failure in Defibrillation?
Success of defibrillation is necessary for the patient to continue his/her life. Failure may mean the loss of the patient or the disability of the patient. Some erroneous applications that cause failure are:
- Incorrect placement of electrodes
- Leaving too little or too much distance between the electrodes
- Insufficient compression of the electrodes
- Incorrect use of gel
- Incorrect energy level
- Small or large electrode selection
- Number of previously applied shocks
- Time between shock applications
- Having hair on the chest
- Failure to disassemble patient-connected devices
- Other people coming into contact with the patient during defibrillation
How to Use an Automatic External Defibrillator (AED)?
Defibrillation is an issue that should be taken very seriously. Even a small mistake can lead to the death of the patient. When applied correctly, it is life saving. There are a number of rules when using an automatic external defibrillator (AED). If these rules are observed, the safety of both the patient and the rescuers is ensured. These:
Before operating the defibrillator, ensure that the patient is not wet. If the patient is wet, it should be dried quickly.
All devices, including respirators used by the patient, should be separated from the patient. if any oxygen concentrator ve ventilator devices should be stopped. Devices should be moved away from the patient.
The patient should not have jewelry, metal accessories or a pacemaker on the chest. The patient can be seriously injured because metals conduct electricity.
The clothes on the patient should be removed or cut quickly. Defibrillator electrodes should be applied to the bare body.
The electrodes must rest either on the patient or on the device. It should not be kept constantly. Also, the electrodes should not touch each other.
One electrode should be placed under the collarbone on the upper right side of the patient's rib cage and the other under the rib cage towards the left side of the heart part.
When the electrodes are placed in the correct position, the device to rhythm analysis starts. Informs with audible and visual commands whether shock is required or if rescuers should continue CPR.
If the device does not need shocking, it means that the patient's heart rhythm has improved. In such a case, CPR applications should not be interrupted and should be continued until the health team arrives.
A few seconds before the moment of defibrillation, rescuers and other people in the environment should get away from the patient for safety. Otherwise, people who are in contact with the patient or the place where the patient sleeps may be electrocuted during shocking.
After the first shock, the instructions given by the device should be followed and CPR practices should be continued. The AED that continues to analyze the heart rhythm will continue defibrillation if necessary. Until the medical team arrives recovery should continue uninterrupted.