Updated on: February 4, 2026
When someone has a sudden cardiac arrest, an Automated External Defibrillator (AED) can help save their life. However, not all defibrillator types are the same. Some of them are designed for public areas and medical experts. Others offer shocks automatically and require a button press. When you know the difference, you can pick wisely.
According to the American Heart Association, in 2021, only 9.1% of out-of-hospital cardiac arrest patients survived to hospital discharge. This low rate clearly shows how important immediate AED use and CPR are in restoring the heart beating and increasing a patient’s chances of survival before help arrives. In this blog, you’ll learn about the defibrillation definition, explore its various types, understand how to pick the correct AED and uncover important maintenance tips to keep the device ready for emergencies.
Read More: AED Laws and AED Requirements by State
An AED is a life-saving and portable device that is used during sudden cardiac arrest. The device monitors the electrical rhythm of the heart. It then tells the rescuer whether or not a shock is required. If it’s needed, it will either prompt you to press a button (semi-automatic) or deliver the shock on its own (completely automatic).
These cardiac defibrillators consist of a built-in computer, a battery, and electrodes (pads). The device can analyze the heart and also uses visual or spoken instructions to guide a user. According to a study from the National Institute of Health (NIH), during cardiac arrest, every minute without treatment cuts the survival chances by 7 to 10%. So, in such situations, CPR must begin immediately, and using an AED right after can significantly enhance the survival chances.
Read More: How an AED Works: Step-by-Step Guide to Save Lives
You will find several types of defibrillator that are used in various settings. Here is a brief description of each of them:
These defibrillator types are put in public spaces, such as offices, airports, schools, or malls. Public access AEDs are made for the general public. Anyone can use these AEDS with minimal training, but basic AED/CPR training is strongly advised. These AEDs use visual and voice instructions to assist users properly. Their main objective is to reach the patient immediately to offer life-saving care before medical help arrives.
These are used by the first responders or the medical staff. Professional AEDs provide additional control, like showing the ECG data. It also lets the operator adjust the energy levels. To use the professional AEDs effectively, users are required to get formal training, as they function in rescue scenarios, hospitals, or ambulances.
Known as one of the most important defibrillator types, it’s designed to analyze the electrical activity of the heart. After that, it provides the user with audio prompts on when to press a button. It will say “no shock” or “shock advised”. This decision maintains a proper balance between automated process and human input, minimizing the blunders while making sure the user remains engaged.
These defibrillator types analyze the heart and, if needed, offer a shock by themselves. You just need to place the pads and then step back. There is no need to press a button like the semi-automatic one. It’s one of the easier AEDs to use, particularly under pressure. Using this AED can lower hesitations during emergencies.
The ICDs are small devices that are placed inside the chest to monitor the heart all the time. These are perfect for individuals who have a high risk of severe heart conditions. It’s also suitable for those who have experienced dangerous heart rhythms before. The device is placed under the collarbone, and the wires are connected to the heart. ICDs can act instantly if the heart beats dangerously and stop sudden cardiac arrest.
These defibrillator types are usually found in several public areas, ambulances and hospitals. They use paddles to give the heart an electric shock. Only qualified medical staff must use them. They also allow physicians to control the shock’s strength and timing, which is essential for complex cases.
ALS defibrillators are powerful machines for use by paramedics and hospital staff. They help treat very sick patients. These devices monitor vital signs like blood pressure, ECG, and oxygen levels while giving shocks if needed. They are found only in ambulances and hospitals.
AEDs aren’t made as separate devices for children. Instead, most standard models include pediatric settings or special electrode pads designed for young patients. Whenever possible, caregivers should use pediatric pads or switch to child mode. These options automatically lower the shock’s intensity, making it safer for a child’s smaller heart.
If pediatric pads aren’t available, adult pads can be used on children under 8 years old or under 55 pounds (25 kilograms), but only when there’s no alternative.
These are like wearable devices or vests. They help monitor the heart rhythm the entire day. If a dangerous rhythm gets detected, they provide shocks immediately. They are prescribed medical devices, mostly for all the high-risk patients and not for the public-use AEDs.
Here is a small comparison table of the various defibrillator types:
| Type of AED / Defibrillator | Who Uses It | Key Feature | Notes |
| Public Access AED | General public / lay responders | Easy to use with voice prompts | Placed in public spaces; designed for emergencies only |
| Professional AED | Healthcare providers | Advanced features, more precise settings | Used in clinics, ambulances, and hospitals |
| Semi-Automatic AED | Lay responders/ workplaces | Guides the user to press the shock button | Often preferred for safety or training purposes |
| Fully Automatic AED | Lay responders/ workplaces | Delivers a shock automatically | Fast and simple; ideal where immediate action is needed |
| Wearable Cardioverter | Prescribed for high-risk patients | Monitors continuously and delivers shock if needed | Worn like a vest; continuous protection outside the hospital |
| Pediatric AED (Child Mode) | Children under 8 years or below 55 lbs | Reduces shock intensity automatically | Standard AED with child pads or child mode; safer for small hearts |
| Implantable Cardioverter-Defibrillator (ICD) | High-risk patients, prescribed by doctors | Implanted inside the chest, monitors the heart continuously | Acts quickly to prevent sudden cardiac arrest |
| Manual External Defibrillator | Trained medical staff | Allows manual control of shock timing and strength | Found in hospitals and ambulances; requires training |
| Advanced Life Support (ALS) Defibrillator | Paramedics and hospital staff | Monitors vital signs and gives shocks if needed | Heavy-duty machines in ambulances and hospitals, for critical patients |
*Infographic*
| Type | Pros | Cons |
| Fully Automatic | Simple to use, faster shock delivery | Less control for trained users |
| Semi-Automatic | Clear prompts, user-controlled shock | Slight delay due to button press |
| Manual AED | Full control, advanced functions | Requires medical training |
| Pediatric AED | Safe for children | Needs correct pads/settings |
| Wearable AED (WCD) | Continuous protection at home | Not for emergency public use |
Although it’s essential to know what defibrillation is, it’s just as important to understand how to pick the correct AED. After all, knowing the concept is one thing, but selecting a reliable device, suited for your setting and easy to use, can make a massive difference during emergencies. The following steps will help select the right one for a particular situation:
If non-medical individuals want to use the AED, they can pick between fully automatic and semi-automatic AEDs. Both of them are suitable and safe for use by the lay responders. A fully automatic AED analyzes the heart rhythm and delivers a shock without prompting, making it useful in high-stress public areas like airports or shopping malls. Semi-automatic AEDs require the user to press a button to deliver the shock, which many workplaces prefer for added safety and training support, such as in offices, schools, or gyms, where staff may have basic CPR or AED training.
The setting where the AED will be installed should guide your choice.
AEDs with clear voice prompts, visual instructions, or screen cues are easier to use under stress. Some models also offer CPR feedback, like metronomes or depth sensors, to improve resuscitation quality. Features like battery status alerts and maintenance reminders can also reduce errors during critical moments.
Apart from knowing the defibrillator definition, you should also learn how to maintain them. You need to change its batteries, inspect internal tests, and change pads. Several AED expenses come up repeatedly, where the pads typically need replacing every 2 to 5 years, and the batteries often last for 2 to 7 years before they need to be changed. You should compare the warranties, ease of services, and replacement parts.
Read More: The Difference Between a Cardiac Arrest and Heart Attack
AEDs are known as life-saving devices. Knowing various defibrillator types will let you pick the correct one based on the emergencies. Make sure to keep them well-maintained and ensure that users are properly trained. In public spaces, opt for simple, user-friendly models that anyone can operate. In clinical settings, select advanced devices that offer greater control for trained professionals. Specialized AEDs for children and wearable options are also available to meet specific needs.
Furthermore, if you want to improve your skills in emergency response, enroll in our PALS Certification training. It will equip you with advanced methods. These methods will help you manage pediatric emergencies perfectly. So, don’t think twice. Get your training today!
1. What is defibrillation, and how does it function?
Defibrillation offers an electric shock to the heart that will restore a normal rhythm during sudden cardiac arrest. Using an AED can make this process safe and effective.
2. Can an AED be used by anyone?
Yes. Most AEDs are designed for all lay responders. The clear voice prompts guide users through each step, making it safe and easy to operate.
3. How often should AED pads and batteries be replaced?
APads typically expire every 2 to 5 years, and batteries last for 2 to 7 years. When you replace them on time, it ensures the device works when it’s needed most.
4. Do the AEDs work on children?
The standard AEDs can be used on children with pediatric pads or by switching to child mode. Adult pads might be used only if pediatric options aren’t available, for children under 8 years or 55 lbs.
PALS Certification is a trusted provider of online life support training, offering PALS, BLS, and ACLS certification and renewal courses. Our flexible training programs follow industry guidelines, offer self-paced learning and instant certification, ensuring providers stay compliant, advance their credentials, and deliver high-quality patient care.
Updated on: February 4, 2026
Updated on: February 4, 2026
Updated on: February 4, 2026
