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Defibrillator Types

Defibrillator Types

From AEDs, ICDs, advanced life support defibrillators, pacemakers, and wearable defibrillators, there is a wide range of medical defibrillation machines that people can use to treat and monitor dangerous heart conditions such as cardiac arrest, life-threatening arrhythmias, ventricular fibrillation, and ventricular tachycardia. Did you know that you can choose between numerous types of machines when you need an electric shock to restore a natural heart rhythm? 

What are these various medical options, and how do you know which one is ideal for you? A common similarity that can be drawn between all systems is that they make use of electrical shocks in the procedure of treating a patient whose heart rhythm is abnormal and places them at risk of experiencing sudden death. Let us take a look at each of these medical defibrillator devices in further detail. 

What Are the Different Types of Defibrillators?

The different medical and health defibrillator types can be divided into four categories, namely:

  1. Advanced life support defibrillators
  2. Automated external defibrillators – AEDs
  3. Implantable cardioverter-defibrillators – ICDs
  4. Wearable defibrillators

Defibrillator Types and Uses

Since there are four types of medical defibrillators, what is each class used for? Do they all serve the same purpose in terms of one’s health? What is the difference between each type on a medical basis?

Advanced Life Support Defibrillators

Advanced life support or ALS defibrillators are used by medical experts in hospitals and emergency medical transport; they allow doctors to control the patient’s heart rate and manually intercede if a shock is required. Additionally, most of these machines have an AED or Advisory feature, which analyzes waveforms and makes shock suggestions based on the advanced algorithms of the device.

Advanced Life Support Defibrillators

Advanced life support devices may be used with pads or electrodes; defibrillation electrodes are the preferred method today because it is a safer and more secure way for the user and provides the shock more evenly and efficiently. The American Heart Association recommends using pads. 

Self-adhesive defibrillator electrode pads are as efficient as gel pads, and one can use them before sudden cardiac arrest to evaluate and administer a shock quickly if required. As a result, self-adhesive pads can be utilized instead of traditional paddles on a regular basis.

Parameters for Advanced Tracking

An ALS defibrillator is also equipped with a range of parameters to assist users in addition to the ability to produce shocks.

Many in-hospital ALS systems would have an external pacing feature, allowing bradycardiac rhythms to be paced externally.

The majority also have SpO2, which is a method of measuring the levels of oxygen in patients through an external sensor.

ALS defibrillators have the following options:

  • Capnography – Carbon dioxide levels are monitored using capnography. The AHA has now designated continuous waveform capnography as a Class 1 recommendation for monitoring ET tube placement.
  • Non-Invasive Blood Pressure (NIBP) – NIBP uses a blood pressure cuff to automatically assess the patient’s blood pressure.
  • Invasive Blood Pressure – IBP stands for invasive blood pressure, and healthcare providers use it during emergency care transportation of patients inside hospitals or by aircraft or ambulance. 
  • Temperature – One needs to keep track of the patient’s temperature. 
  • 12-Lead ECG – STEMI can be quickly identified and classified using a 12-lead ECG, which is commonly used by paramedics in the field. The ECG reading may be sent to necessary hospitals, alerting cardiologists that a patient in need of emergency care is on the way so that the situation can be dealt with as quickly as possible. 
  • CPR Assistance – An increasing number of modern ALS defibrillators offer CPR assistance. It has become evident that excellent CPR is essential to improving the outcome of resuscitation; however, even highly qualified clinical experts have discovered that providing good reliable CPR is challenging. As a result, there is an increasing awareness of the need for defibrillation devices to be capable of not only providing a shock but also assisting with the delivery of optimum blood flow circulation support.

Automated External Defibrillators – AEDs

An automated external defibrillator (AED) is equipped for ordinary people and individuals who have undergone basic CPR to use, first aid, AED, and life support training. You can find them in schools, employment offices, shopping centers, airports, sports arenas, colleges, dental offices, entertainment places, and other public locations.

Automated External Defibrillators

They assist rescuers through the electrode application process and automatically evaluate the heart rate or abnormal heart rhythms of the patient to warn the user or administer a shock to the heart themselves. Many devices would also instruct people to begin CPR, but only a few AEDs on the market instruct users on performing chest compressions at the proper pace and depth. For example, the ZOLL AED Plus coaches the user. This capability is most likely going to be expanded to other manufacturers and defibrillation devices as the value of CPR delivery is increasingly recognized as a vital part of successful treatment and rescue.

A few AEDs that are efficient with restoring a normal cardiac rhythm to a beating heart after a shock include:

Implantable Cardioverter-Defibrillators – ICDs

Implantable cardioverter-defibrillators (ICDs) are surgically inserted into the patient’s chest, and they offer protection to patients at high risk of sudden cardiac death. An ICD is connected to the patient’s chest or heart via thin medical wires. Patients who have either an established medical condition that puts them at risk, or who have previously witnessed ventricular fibrillation or ventricular tachycardia episode, fall into this category. The American Heart Association website has a great deal of information regarding these medical defibrillation machines that help restore a normal heart rhythm in patients who experience life-threatening arrhythmias.

An implantable cardioverter-defibrillator, or ICD, is an excellent way to monitor a person’s heartbeat and cardiac rhythm. An ICD device needs to be implanted by a doctor or health and medical professional to ensure that it can deliver a safe shock if necessary. The procedure involves ICDs delivering a shock when it detects an uncontrollable heartbeat or heart rhythm. 

Research proves that people who experience ventricular tachycardia or ventricular fibrillation have discovered that an ICD is helpful in reducing the risk of death or the need for surgery or another procedure. An ICD device may assist in preventing cardiac arrest in people who have not encountered but face the possibility of life-threatening ventricular arrhythmia or related conditions. 

Wearable Defibrillators

Patients at risk of sudden cardiac death can benefit from the use of wearable defibrillators. If an individual is at risk of sudden cardiac arrest due to ventricular tachycardia or ventricular fibrillation, and they are not candidate for an implantable cardioverter-defibrillator, ICD, they should use a wearable cardioverter defibrillator (WCD) for external analysis, evaluation, and to monitor defibrillation shocks. A wearable defibrillator offers tracking as well as defibrillation support. Where a patient’s situation prevents or delays implantable cardioverter-defibrillator, ICD, implantation, or when an indicated ICD must be removed, you can use a wearable defibrillation device as a bridge to deliver the required treatment. These defibrillator systems are used to avoid sudden cardiac death in high-risk intervals following a myocardial infarction, coronary revascularization, or a new diagnosis of heart failure.

What Are the Differences Between Internal and External Defibrillators?

An internal defibrillator and an external defibrillator are basically the same systems that deliver the same operation in two various cases. An internal defibrillator, or implantable cardioverter-defibrillator, is so-called because it is inserted into the patient’s body and can constantly monitor the heartbeat and heart rhythms in the chest, providing automatic defibrillation if a life-threatening decline in the heart rate is observed. Alternatively, manufacturers designed an external defibrillator to be a portable device that can be used in the event of cardiac arrest and can be automatic or manual. 

In most instances, an automated external defibrillator, AED, is a portable monitor system that is strategically positioned, often in wall cabinets, in areas where large groups of people congregate; office buildings, sports arenas, hotels, churches, entertainment spaces, and even a hospital often has one or more external defibrillators readily available which leads to safety measures being implemented. An implantable cardioverter-defibrillator (ICD), or internal defibrillator, is usually administered by a doctor to people at risk of having a life-threatening heart attack or cardiac arrest.

The aim of getting an accessible external defibrillator in every public space is to treat sudden cardiac arrest, ventricular arrhythmias, ventricular tachycardia, or other cardiac rhythm issues in the chest. A sudden cardiac arrest, unlike a heart attack, can affect any individual at any moment, regardless of their heart health or fitness. It is a life-threatening situation, and getting an external defibrillator device can mean the difference between life and death. The heart starts to die at a rate of 10% per minute when sudden cardiac arrest occurs, which means that a period of 10 minutes equals death. Permanent brain damage can happen in five minutes, and the chances of harm increase with each passing second.

When Do You Need a Defibrillator?

If you have ventricular fibrillation, you are going to need an implantable cardioverter-defibrillator (ICD). When the lower chambers of the heart in a person’s chest do not contract strongly enough to pump blood across the human body, cardiac arrest occurs. If you have ever had a cardiac arrest due to ventricular fibrillation, arrhythmia, or another reason, you are going to need an implantable cardioverter-defibrillator or ICD.

When Do You Need a Defibrillator

You may require an echocardiogram to assess your heart’s pumping capacity in your chest, or ejection fraction, if you do not have a history of those issues but are at increased risk of them due to a heart attack or some type of heart disease. If your ejection fraction is less than 35 or 30 percent, depending on whether you have had a previous heart attack, you are probably going to need an implantable cardioverter-defibrillator (ICD) device. If it is higher, inquire as to why your doctor believes you need an ICD device.

A doctor is going to recommend ICDs if:

  1. You survived sudden cardiac arrest caused by ventricular fibrillation.
  2. A patient has structural heart diseases, ventricular fibrillation, arrhythmia, or ventricular tachycardia that results in fainting.
  3. Patients recover from a heart attack with an ejection fraction of 35% or lower.
  4. One experiences an ejection fraction and dilated cardiomyopathy of 35% or lower.
  5. There are previous instances of ventricular tachycardia
  6. A person goes through unexpected fainting, dilated cardiomyopathy, and reduced left ventricular fibrillation
  7. There are signs of one or more high-risk factors associated with sudden cardiac arrest
  8. People are victims of hypertrophic cardiomyopathy
  9. There are heart or cardiac rhythm issues that require shocks
  10. Individuals experience Chagas disease, cardiac sarcoidosis, or giant cell myocarditis

When Do You Not Need a Defibrillator?

An ICD health device is not always the solution to your beating heart issue, which is where a device such as a wearable defibrillator may provide better results. A person should not have a defibrillator when:

  1. Their life expectancy is one year or less.
  2. They experience continuous cases of ventricular arrhythmia, tachycardia, or fibrillation
  3. There is a history of psychiatric illnesses – the device may interfere with the current medical care, which leads to more severe issues.
  4. The causes of fainting are unexplained or cannot be determined
  5. One encounters ventricular arrhythmia that a doctor can cure by catheter ablation or another related surgery or procedure
  6. An individual has a chest or heart condition that results from a reversible reason, such as medicine 

What Is the Best Defibrillator?

The various types of defibrillators serve different purposes; hence, it is challenging to identify one better than the others. Instead, you should pay attention to specific characteristics that are going to suit your needs or preferences, such as:

  • Price
  • Pads of electrodes – External devices
  • Batteries
  • IP Rating 
  • Size


The types of defibrillators, like every other technology, have a wide range of prices. Consider your needs, preparation, and how much and under what conditions you are going to use the defibrillator when deciding on a price within your budget.

For example, the cost of a recertified Cardiac Science Powerheart G3 is much more affordable than the cost of a new Zoll AED Pro

Pads or Electrodes

Defibrillator pads are specific to AEDs. One-size-fits-all is not a choice when it comes to automated external defibrillators, or AED pads. AED pads are divided into two categories: adults and children or infants. Consider the category you are most likely to use the AED on when making your order. It is doubtful that you need children’s pads if you install the AED in a retirement community, for example. If the AED would be used in a classroom at a school, one can consider purchasing an AED kit that includes both adult and children’s pads.


Almost every single defibrillator manufacturer has a proprietary battery that is patented for use only in their medical defibrillators. Although the majority of AED batteries are non-rechargeable, rechargeable defibrillation devices are also accessible. Certain defibrillators, such as the Zoll AED Plus, also operate with regular 123 lithium batteries.

Additionally, how you choose to use your device should decide whether you want a non-rechargeable or rechargeable battery. Hence, if you are an expert who uses an AED daily, a rechargeable battery could be the best option for you. Rechargeable training machines, such as the Defibtech Lifeline AED Trainer, can also be useful to CPR and AED trainers. If you only use the defibrillator occasionally, a low-maintenance non-rechargeable battery with an extended lifespan could be the better option.

Note that a fully charged and up-to-date defibrillator battery is vital to the device’s proper operation! 

IP Rating

An IP code is assigned to each defibrillator. This code, also known as the “International Security Rating” or “Ingress Protection Rating,” classifies the standard of protection provided by an electrical device or machine (such as a defibrillator) against dust and liquid. For example, when buying an outdoor AED, look for one with a higher IP rating and a waterproof Pelican Case.


Size does not matter if you bolt an automated external defibrillator, or AED cabinet to the wall and forget about it until compliance management software sends you a maintenance alert. If an automated external defibrillator is going to accompany an individual everywhere they go, the person is going to want to look for something light and portable, like the Philips HeartStart OnSite AED.

If you are looking at an implantable cardioverter-defibrillator or ICD, you want to find something small and compact as it is implanted in your body under the skin and muscle. 

How Many Joules Does an AED Deliver?

Escalating and non-escalating procedures are used by automated external defibrillators to administer an electrical shock. Both styles are available from various defibrillator manufacturers. Individuals need to determine which defibrillator types are best for them.

Some medical professionals believe that defibrillation can be accomplished with a continuous flow of low-energy output or electrical activity. Other doctors believe that an automated external defibrillator, AED device with escalating electrical energy levels is needed to shock patients who do not respond to the first or second shock to the heart.

Different types of defibrillators offer various levels of electrical activity and shocks. The highest level of available energy is 360 joules, which is a beneficial factor to look for when choosing your defibrillator and its’ shock ability, as you want the option of higher energy currents to prevent sudden death. Related research shows that 360 joules improve the chances of shock success. However, there are defibrillators that only deliver a shock of between 150 to 200 joules. 

What Are Joules? 

When looking at things from a scientific perspective, one unity of electrical energy is equal to the amount of work performed when a current of one ampere passes through a resistance of one ohm for a second. 

Joules are pronounced exactly the same as jewels; however, you are probably only going to find a doctor or scientist as intrigued with joules instead of jewels. When it comes to saving a life, joules are a valuable factor to consider. Joules is the unit of measurement used to monitor and deliver the electrical activity and shock provided by an automated external defibrillator, AED. The joules in the electric shock to the heart are the life-saving factor when a patient experiences sudden cardiac arrest SCA, abnormal heart rhythms, ventricular fibrillation, or heart failure. Sudden cardiac arrest happens when a patient’s heart starts to quiver or fibrillate uncontrollably, resulting in abnormal heart rhythms. An individual who does not have a normal heart rhythm or heartbeat is going to collapse, lose consciousness, have their heart stop beating, which ends in them no longer breathing. When no treatment is provided, and there is nobody to monitor the situation, the victim may experience sudden death. Under these circumstances, an AED, ICD, or other type of defibrillator is the only way to restart the person’s heart or restore a normal heart rhythm. 

A 19th-century physicist, James Prescott Joule, researched and studied the amount of heat generated by an electric current and figured out the first law of thermodynamics. Joules are essential in AEDs because they specify the number of electric shocks transmitted from the AED to the patient, passing through the pads. The electric shock to the heart is what restarts it and restores a normal heart rhythm. 

Whatever defibrillator types you choose for your AED program or services, it is crucial to note that having an AED on-site and qualified first aid responders available is critical for the health and safety of your workers and other individuals. Sudden cardiac arrest knows no bounds, striking the young and elderly, safe and sick, wealthy and impoverished alike.

The Final Verdict

A factor that leads up to cardiac arrest, ventricular fibrillation, ventricular tachycardia, abnormal heart rhythm, or ventricular arrhythmia often indicates that there is something wrong with the heart’s electrical patterns or system. Hence, people need a defibrillator shock to restore the natural heart’s rhythm. There are a few types of defibrillators to choose between. An advanced life support defibrillator, AED, implantable cardioverter-defibrillator (ICD), a wearable defibrillator, and a pacemaker. Which option is the most suitable for you? 

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