What is the Difference Between a Fully Automatic AEDs, Semi-Automatic AEDs, and Manual Defibrillators?

by | Apr 5, 2024

Automated External Defibrillators are portable devices designed to deliver potentially life-saving electrical shocks to individuals experiencing sudden cardiac arrest. These devices are becoming increasingly common in public spaces, workplaces, and healthcare facilities due to their ability to quickly assess heart rhythms and provide prompt intervention during emergencies. According to the CDC, approximately 356,000 cases of sudden cardiac arrest occur outside of hospitals in the United States each year. An AED can significantly increase the chance of survival in sudden cardiac arrest by up to 70% when used promptly alongside CPR. 

Here I delve into the differences between a Semi-Automatic AED, Fully Automatic AED, and Manual Defibrillators, exploring their features, advantages, and considerations for implementation in various settings. In short, a semi and fully automatic AED are for bystanders while a manual AED is for hospital use. Then the difference between fully auto and semi auto requires you to click the shock button while the fully auto will deliver the shock itself if it is needed. Below, I will cover this topic in greater detail. 

Here Are the Topics We Will Cover:

What is an Automatic AED and Semi-Automatic AED?

Automatic AEDs are intelligent machines specifically designed to swiftly analyze the heart’s rhythm during a cardiac arrest scenario. They are equipped with advanced algorithms that assess the heart’s electrical activity and determine if a shock is required to restore normal rhythm. These devices, characterized by their simple-to-use interface, simplify the rescue process even for those with limited training or experience in emergency situations. With their user-friendly design, automatic AEDs empower us to take immediate action and potentially save lives in critical moments of need.

Difference Between a Fully Automatic AED and a Semi-Automatic AED

The main difference between a fully automatic AED and a semi-automatic AED lies in the delivery of the electrical shock. In a fully automatic AED, the device automatically analyzes the heart rhythm and delivers a shock if it detects a shockable rhythm without the need for user intervention. Conversely, in a semi-automatic AED, although the device automatically analyzes the rhythm, the user must manually trigger the shock delivery by pressing a button if advised by the device.

Pros and Cons of Automatic AED and Semi-Automatic AED

Automatic AEDs offer several advantages and are great tools to help save lives. Having them in as many places as possible will help save more people who fall victim to sudden cardiac arrest.

Pros of Automatic AED and Semi-Automatic AED:

  • User-Friendly Operation: Automatic AEDs are designed for simplicity, featuring clear voice prompts and visual instructions that guide us through the rescue process step by step. This user-friendly interface enables even untrained individuals to effectively administer life-saving treatment during a cardiac emergency. 
  • For a fully Automatic AED, the device automatically analyzes the heart rhythm and delivers a shock if needed without requiring user intervention, it minimizes the potential for user error, especially in high-stress situations. This feature makes fully automatic AEDs ideal for locations where individuals with little to no levels of training may need to use them, such as grocery stores and gas stations. Additionally, fully automatic AEDs can be particularly beneficial for untrained bystanders who may be hesitant or unfamiliar with using medical equipment during emergencies.
  • Rapid Response Time: Automatic AEDs are programmed to quickly assess the heart rhythm and deliver a shock if necessary. Their swift response time can significantly increase the chances of survival for someone experiencing sudden cardiac arrest, as every second counts in critical situations.
  • Reduced Error Margin: The automated functionality of these devices minimizes the risk of human error during the resuscitation process. By following the prompts provided by the AED, anyone can perform CPR and deliver a shock with confidence, knowing that the device is accurately analyzing the patient’s condition.
  • Accessibility in public places like churches, airports, schools, and shopping centers for immediate access during emergencies. Find the lightning bolt sign the next time you are around these areas!

Cons of Automatic AED and Semi-Automatic AED

  • Cost: Automatic AEDs typically come with a higher price tag compared to manual defibrillators. The initial investment required to purchase these devices may pose a financial challenge for some organizations or individuals, especially for smaller businesses or community groups. 
  • Dependency on Battery Power: Automatic AEDs rely on battery power to function effectively. While modern AEDs are equipped with long-lasting batteries, there is still a risk of the device losing power during prolonged periods of storage or in the event of a power outage.
  • Limited Adjustability: Automatic AEDs are designed to provide standardized treatment protocols based on preset algorithms. While this ensures consistent and reliable performance, it may limit the device’s adaptability to unique patient scenarios or specific clinical needs.

What is a Manual Defibrillator?

A manual defibrillator is a medical device used to deliver an electrical shock to the heart in order to restore normal heart rhythm during cardiac arrest or life-threatening arrhythmias. Unlike automatic AEDs, which analyze the heart rhythm and deliver a shock automatically, manual defibrillators require the user, typically a trained medical professional, to interpret the heart rhythm and determine when to administer the shock manually. These devices play a crucial role in advanced cardiac life support (ACLS) protocols and are commonly used in hospital settings, emergency departments, and critical care units where immediate access to comprehensive cardiac care is essential.

To be clear, manual defibrillators are only for trained professionals and not for bystanders.

Pros and Cons of Manual Defibrillators:

Manual defibrillators offer several advantages and disadvantages compared to automatic AEDs. Understanding these pros and cons is essential for healthcare professionals and emergency responders who may encounter cardiac arrest situations requiring defibrillation.

Pros of A Manual Defibrillator:

  • Versatility: Manual defibrillators provide healthcare providers with greater control and flexibility in managing cardiac emergencies. They offer a wide range of settings and options, allowing providers to customize treatment based on the patient’s specific condition and response to therapy.
  • Advanced Features: Manual defibrillators are equipped with advanced features such as synchronized cardioversion, which allows healthcare providers to deliver a shock at a specific point in the cardiac cycle to treat certain types of arrhythmias effectively. These devices also offer adjustable energy levels, allowing providers to deliver higher or lower doses of electrical energy as needed. These specific types of treatments are not available in automatic AEDs. 
  • Continuous Monitoring: Many manual defibrillators include integrated monitoring capabilities, allowing healthcare providers to continuously assess the patient’s cardiac rhythm, vital signs, and response to treatment. This real-time feedback enables providers to make informed decisions and adjust therapy as necessary throughout the resuscitation process.

Cons of a Manual Defibrillator:

  • Complexity: Manual defibrillators are more complex to operate compared to automatic AEDs. Healthcare providers must undergo specialized training and certification in advanced cardiac life support (ACLS) to effectively use manual defibrillators and interpret electrocardiogram (ECG) readings accurately. Healthcare providers must be proficient in identifying various cardiac arrhythmias, interpreting ECG waveforms, and determining the appropriate treatment algorithms for each patient.
  • Limited Accessibility: Manual defibrillators may not be as widely available in public settings as automatic AEDs due to their complexity and the need for trained personnel to operate them safely and effectively. This limitation can potentially delay access to life-saving defibrillation in out-of-hospital cardiac arrest situations.

Do You Want an Automatic, Semi Automatic, or Manual AED? 

Choosing between a semi automatic, fully automatic, or manual AED depends on various factors, including the intended use, available resources, and the level of training and experience of potential users. In short, unless you work in a hospital setting, you will always want an automatic or semi-automatic AED, and even in many hospital settings, people are transitioning away from manual defibrillators.

Here are some considerations to help determine which type of AED may be most suitable for your specific needs:

User Training and Experience

Automatic or Semi Automatic AEDs are designed to be user-friendly and can be operated by individuals with minimal training or experience. For most organizations this is the defibrillator for you since most organizations consist of laypersons or non-medical personnel who may need to respond to sudden cardiac arrest emergencies, an automatic AED may be the preferred option due to its simplicity and ease of use.

As discussed earlier Automatic or Semi Automatic AEDs are both great life saving devices, but fully automatic are a little easier to use and can be great options for the everyday person to be able to use effectively. However semi automatic are still great options. View our selection of AEDs here or contact us to learn more about how to purchase an AED. 

Clinical Capabilities

Automatic AEDs are designed primarily for basic cardiac rhythm analysis and defibrillation, making them suitable for laypersons and non-medical users in public settings. In contrast, manual defibrillators offer advanced features such as synchronized cardioversion and manual defibrillation, which may be necessary for managing complex arrhythmias and cardiac arrest situations in healthcare settings with trained personnel.

Regulatory Requirements

Consider any regulatory requirements or guidelines that may influence your AED selection process. In some jurisdictions, specific industries or healthcare facilities may be subject to regulations or standards that dictate the type of AEDs to be used, training requirements for users, and maintenance protocols. Ensure compliance with relevant regulations and standards when choosing an automatic or manual AED for your organization.

How Do I Use an AED?

The most important thing to remember when using an AED is to listen to the AED. It will clearly walk you through the process of using the device you just need to listen to every step it guides you through. Additionally it can’t guide you through anything until you turn it on. It is easy to forget to turn it on in the stress of the moment, so make sure to remember that key step. Additionally, there is no replacement for hands-on practice you get in our AED class, however I will explain the process below in addition to the guide in our video.

  1. Assess the Scene: Ensure the safety of the rescuer and the victim by assessing the scene for any potential hazards or dangers. If the environment is safe, proceed to approach the victim and assess their responsiveness.
  1. Activate Emergency Medical Services (EMS): If the victim is unresponsive and not breathing normally, immediately activate EMS or call for help by dialing the local emergency number or 911. Time is critical during cardiac arrest emergencies, so it’s essential to initiate the chain of survival as quickly as possible.
  1. Retrieve and Prepare the AED: Locate the nearest AED and bring it to the victim’s side. Most AEDs are stored in clearly marked cabinets or designated locations for easy access. Once you have retrieved the AED, power it on and follow the visual and auditory prompts provided by the device.
  1. Attach the Electrode Pads: Open the AED carrying case and remove the electrode pads. Peel the pads from their packaging and firmly attach them to the victim’s bare chest as indicated by the diagrams on the pads. Place one pad on the upper right side of the chest, just below the collarbone, and the other pad on the lower left side of the chest, just below the armpit, below and to the side of the heart.
  1. Analyze the Heart Rhythm: Once the electrode pads are securely in place, the AED will automatically analyze the victim’s heart rhythm. Ensure that no one is touching the victim during the analysis process. The AED will prompt you to “stand clear” while it evaluates the heart rhythm.
  1. Follow Voice Prompts: Based on the analysis results, the AED will provide clear voice prompts and visual instructions to guide you through the defibrillation process. If a shockable rhythm like ventricular fibrillation or pulseless ventricular tachycardia is detected, the AED will instruct you to deliver a shock by pressing the designated button. It is crucial to listen to the prompts and not get ahead of the device because that is where things usually go wrong.
  1. Perform CPR as Directed: After delivering a shock, or if the AED advises against shock delivery, immediately resume cardiopulmonary resuscitation (CPR) according to the AED’s guidance. This means to preform high quality CPR at the correct compression-to-ventilation ratio (30 compressions to 2 breaths) and continue CPR until EMS arrives or the victim shows signs of recovery. Most AEDs will beep at the correct speed of compressions to help you stay at the right rhythm which is 100-120 beats per minute. Some devices like the Zoll 3 will even give you feedback on the quality of your compressions.
  1. Deliver Another Shock As Directed: It will take multiple shocks to restart the victim’s heart, so after performing CPR for about 1-2 minutes the device will tell you when to pause CPR so it can deliver the next shock. Keep doing CPR until the device clearly tells you to pause, but at that point hands need to be off and get ready to deliver the next shock. 
  1. Stay with the Victim: Provide reassurance and support to the victim until EMS personnel arrive on the scene. Continue to follow the AED’s prompts and perform CPR as needed until advanced medical care is available.

How to Get CPR, First Aid Certified, and AED Training

At First Response, we offer affordable and accessible courses designed to instruct and certify anyone with the skills of how and when to utilize the AED. This course will not only help you know how to use an AED but also know how to respond in First Aid and CPR emergencies. If your facility has an AED on-site this level of training is required for all expected users. If you would like to host a CPR, First Aid, and AED class request one here or sign up for a self paced blended one here.

View all of our class offerings here, including Fire Safety, CPR and First Aid, BLS, and Bloodborne pathogen.If you have any questions, contact us here.

About First Response

First Response provides CPR, First Aid, and Fire Safety training to clients across Georgia and South Carolina for over 23 years. We believe training should be relevant, informative, and fun! Feedback from our clients consistently shows that they not only enjoy our classes, they learn something new–even for folks that have taken the class many times before.

Contact us to book a class for your facility, or sign up for a class here.

About the Author

<a href="https://www.firstresponsecpr.com/blog/author/calvin/" target="_self">Calvin Go</a>

Calvin Go

CPR, First Aid, and Fire Safety Instructor

Calvin has taught CPR, First Aid, and Fire Safety for First Response since June 2023. He is also medical student working towards his PHD. His experience as a medical student and safety instructor brings a unique perspective into his articles.

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