Life-Saving Training Blog

 

When to Use an AED: Common Questions and Answers

by  Bob Elling     Mar 12, 2025
aeds-common-questions

Over the course of my career as an EMS provider some of the most exciting moments have been witnessing a clinically dead person’s return of spontaneous circulation (ROSC) immediately after being administered a shock. As we have learned, a successful resuscitation is not just based on a “miracle” moment. It is a function of a community that has spent considerable time and effort to strengthen the links in the chain of survival. 

I learned many years ago that for the best trained EMTs to have the best odds for ROSC, the community should have a large number of citizens trained in the skills of CPR and be comfortable using the easily accessible nearby AED. Plenty of great advice has been written about strengthening the links in the chain of survival in each community. We know what to do, or can easily find out, but the hard work is implementing so we do not have to rely on a “miracle” moment, rather everyone knows their role and consistently practices their role! 

Let’s review some history, statistics, and common questions and answers on AEDs.    

A Brief History of AEDs
In 1849 Ludwig and Hoffa defined the concept of fibrillation of the ventricles. In 1900, Prevost and Batelli began research on ventricular fibrillation (VF) in the dog lab. They discovered a strong electrical current can be used to defibrillate. Further research by Wiggers and Wegria helped determine the amount of current for successful “counter-shocking” of VF.  

Development of defibrillators began in the 1920s and in 1947 Beck performed the first successful human defib using internal paddles on a 14-year-old boy during chest surgery. In 1956, Zoll performed the first successful human external defib using a 15-amp AC current. In 1961, Kleiger and Lown found AC current could terminate ventricular tachycardia (VT) and demonstrated the superiority and safety of DC over AC for defibrillation.  

In 1966, ambulances with physicians in Belfast performed successful prehospital defibrillation. Then in 1969, EMTs without the presence of a physician was performed in Portland, Oregon.

In the early 1970’s, Diack, Welborn and Rullman were testing prototype AEDs. Thanks to the advanced capabilities of computer technology, these defibrillators, marketed by the Cardia Resuscitator Corporation, were developed to take and interpret the ECG and proceed to shock the patient. Prehospital trials began in 1980 in Brighton, England using the Heart Aid. In 1982, the US FDA gave approval for EMT-defibrillation clinical trials in Washington, Iowa, Minnesota and Tennessee.

These “automatic” units were soon replaced with “automated” units which recommended the shock but did not actually deliver the shock till the operator clears the patient and presses the shock button. Initially, these units were called semi-automatic units but today the term used is AED. So technically, the A in AED stands for automated and NOT automatic!

Computer technology had advanced such that the device could recognize a shockable rhythm, highly likely to be found on a pulseless patient. This advance meant that the ECG screen was not needed and the units became much smaller and lighter. In addition, since interpreting the ECG was no longer needed, the devices could be applied by EMTs, EMRs, or other responders as well as the lay public trained in the skills of CPR and use of the AED.

In the 1990s, AED use expanded to many police and first responder agencies as well as the FDA approval of lay personnel use throughout the USA.

Over the next decade there were many State and local laws enacted to provide for Good Samaritan coverage as well as requirements on where AEDs should be placed for the trained public to access them (i.e. health clubs, government buildings, swimming pools, beaches and parks, airports, sports and concert venues). In May of 2003, thanks to the advocacy of AHA and Louis Acompora Foundation (LA12.org), New York was the first State to require AEDs in the schools!

Statistics Worth Noting
In my humble opinion, the AED is probably the most studied and significant life-saving device used in prehospital care in the last 35 years! Here are just a few of the stats worth noting:

  • Sudden Cardiac Arrest is the #1 killer of student athletes in the USA. 

  • Majority of adult out-of-hospital cardiac arrests (OHCA) occur at a home or residence (71.0%).  

  • A large number of adult OHCA occur in public settings (18.2%). 

  • According to 2023 US data for adult OHCA: 

  • Survival to hospital discharge was 10.2% 

  • For EMS-treated non-traumatic OHCA:  

  • Bystander witnessed adult arrests had 15.4% survival to hospital discharge 

  • 9-1-1 responder witnessed arrests had an 18.2% survival to hospital discharge. 

  • Chance of survival while waiting for EMS during a cardiac arrest decreases by 10% every minute without CPR. 

  • Immediate CPR and use of an AED can double, or even triple, survival rates. 

  • Of people in cardiac arrest who receive a shock from an AED in the first minute, 9 out of 10 live.  

  • Bystanders administer CPR about 40% of the time and AEDs even less so. This is an area where training the public in your community can make a big difference! 

Common AED Questions and Answers
Q: What is an AED and what does it do?
A:  An AED is an “automated external defibrillator.” Today’s units are lightweight, portable, and easily operated by those with limited training. They have simple voice commands for the operator to apply electrode pads to the victim’s chest so the AED can analyze the heart rhythm. The AED will advise CPR if there is no shockable rhythm. If there is a shockable rhythm the AED will advise not to touch the patient and press the shock button and then advise to resume CPR.

Q: Why is the use of an AED important to use in conjunction with CPR?
A: If the patient is in cardiac arrest cardiac chest compressions must begin right away. This will help to circulate blood to the brain, heart and lungs and buy a few moments. The cardiac rhythm must be analyzed to determine if the patient has a shockable rhythm such as VF or pulseless VT. If a shockable rhythm is found the AED will prompt the operator to deliver a shock.  Chances of survival decrease about 10% for each minute that goes by without CPR and defibrillation.

Q: Does the AED “jump start” the heart?
A:  Actually, in combination with quality chest compressions, the AED delivers a shock to the patient in VF or pulseless VT. The shock momentarily “stops” the heart’s lethal rhythm so that the heart’s pacemaker can take back over with a normal heart rhythm that is able to provide circulation.

Q: Who can use an AED?
A: Anyone who has been trained in CPR and oriented to the simple operation of an AED. This training to save a life takes very little time but is very, very important.

Q: How do you know it's the right time to use an AED?
A: The victim is found to be unresponsive; CPR has been initiated. Assure 9-1-1 has been alerted and send someone to get the AED. As soon as the AED arrives use it. Do not wait for police or fire or EMS responders to arrive on the scene to use the AED.

Q: Can I be shocked if I use an AED correctly?
A: If you use the device as the voice prompts instruct on a patient in cardiac arrest you will not be shocked. The AED will analyze and charge up if a shockable rhythm is found but you are the one who clears the patient and then presses the button to actually deliver the shock.

Q: Will I harm a person if I use an AED on someone who doesn't need it?
A: If the patient is found unresponsive and the AED is applied and recommends a shock you will not harm the patient. If a shock is delivered CPR should be started unless the patient becomes responsive. Then assess their ability to breathe and alert the EMS responders.

Q: Can a young person use an AED?
A: Yes, if trained in CPR and the simple operation of the AED. Most schools have public access AEDs and do training in their use.  

Q: If I call an ambulance, should I wait for it to arrive or use an AED in the meantime?
A: Once again, follow your training in CPR and the use of the AED. Make sure 9-1-1 has been called and if there is an extra helper have them meet the responders to help them find your location quickly. If you feel you need some extra encouragement when calling the 9-1-1 dispatcher leave the phone on speaker and they should be able to talk you through the treatment.  

Q: Who should consider owning their own AED?
A: The resuscitation guidelines do not endorse routine home AED installation due to insufficient evidence of benefit. However specific patients or their family may want to discuss this question with their physician based on their medical history. If their physician thinks it would be appropriate, in addition to family training in CPR, they can write a prescription to purchase an AED. That does not mean it will be covered by health insurance. Some states have a law making a portion of the AED costs a tax deduction so check with your accountant on this one.

Q: How much does an AED cost?
A: At ECSI we do not recommend one device over another. The AED you use should be simple, easy to use and FDA approved. The costs depend on the brand and type of use expected (i.e.: home, business, first responder agency). Don’t forget a set of replacement PADs (which have a shelf life) and the battery will need to be replaced in a few years. Estimate approximately $2000. To $3000. 

Q: Can an AED be used on a child?
A: The guidelines call for standard AED use on patients over 8 years old. For a child 1 to 8 years old pediatric pads are used which are designed to decrease the dose of the shock (pediatric-attenuated pads).  

Q: In 2024, the Cardiomyopathy Health Education, Awareness, and Research, and AED Training in the Schools (HEARTS) Act was signed by President Biden. What was the purpose of the law and how can this help schools in your community?
A: Thanks to the Smart Hearts Coalition, the AHA You’re the Cure network, Chasing M’s Foundation, and advocates like Damar Hamlin, the HEARTS Act is now the law. 

The law established a series of programs and requirements relating to cardiomyopathy. Specifically, the Department of Health and Human Services must disseminate information about cardiomyopathy and the use of AEDs to certain school professionals, families, and others, and it must develop specified risk assessment tools for cardiomyopathy. In addition, the CDC must report on certain research and surveillance activities, and the National Institutes of Health must report on its research relating to cardiomyopathy.  

The law also establishes a grant program to provide CPR training and AEDs in public schools. 

As I see it…for what it’s worth!
Advocacy for laws requiring AEDs and CPR training in our schools, at sports events and large public gatherings has been definitely worthwhile. In retrospect, rather than taking the “this type of public building and that type of public building (i.e.: gyms and health clubs and government offices) approach,” if we were starting over, I think it would have made more sense to place the AED requirement in the uniform building codes (where fire extinguishers and appropriate signage are required).

Clearly, AEDs properly placed, managed and both emergency services providers as well as the general public trained in CPR can strengthen the chain of survival and save lives. 

If you and your entire family do not know how to do CPR and how to use the AEDs throughout your community it is high time to learn how. If you are not sure how to accomplish this contact your local rescue squad or fire department for the location of their next CPR and AED training.

CPR and AED Training Organizations
Aside from your local Rescue Squad, Fire Department, hospital or community college, there are many organizations where you can learn more about CPR and AED training. Here are just a few: 

Summary
In summary, consider a few important lessons we have learned about AEDs along the way: 

  • Just because a law requires the AED has to be in places in a public venue/building does not simply save lives. Some organizations have locked the AED in an office where it may not be easily accessible when needed. 

  • Just as important as having the AED is having someone who takes the responsibility for checking the AED and its contents on a regular basis. 

  • Even though AEDs are simple to use by following the voice prompts, providers should be trained in the skills of CPR as well as how to apply and use the AED in your office. 

  • Signage counts when seconds count. Make the AED placements very obvious! 

  • Learn CPR and remember that situational awareness not only includes safety risks but also the location of the nearest AED!

References/Resources:

  • Martin SS, Aday AW, Allen NB, et al; on behalf of the American Heart Association Council on Epidemiology and Prevention Statistics Committee and Stroke Statistics Committee. 2025 Heart disease and stroke statistics: a report of US and global data from the American Heart Association. Circulation. Published online January 27, 2025. 

About the author
Bob Elling, MPA, Paramedic (retired) – has been a career paramedic, educator, author, and EMS advocate for 5 decades. He was a paramedic with the Town of Colonie EMS Department, Albany Times Union Center, and Whiteface Mountain Medical Services. He was also an Albany Medical Center Clinical Instructor at the HVCC Paramedic Program. Bob served as AHA National/Regional Faculty and participated in many successful life-saving legislative campaigns with the You’re the Cure Network. He also served as paramedic and lieutenant for New York City EMS, a paramedic program director, and associate director of New York State EMS Bureau. He has authored hundreds of articles, videos, Blogs, and textbooks to prepare EMS providers for their career. Bob is the ECSI Medical Editor for the CPR and First Aid Series, Co-Author of EVOS-2, and Co-Lead Editor of Nancy Caroline’s Emergency Care in the Streets.

Standard First Aid, CPR, and AED Eighth Edition

Standard First Aid, CPR, and AED, Eighth Edition is ideal for use within training courses designed to certify individuals in first aid, CPR, and AED. This student manual is the center of an integrated teaching and learning system that offers many resources to better support instructors and prepare students to learn life-saving skills.

Request More Information
Standard First Aid, CPR, and AED Eighth Edition

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When to Use an AED: Common Questions and Answers

by  Bob Elling     Mar 12, 2025
aeds-common-questions

Over the course of my career as an EMS provider some of the most exciting moments have been witnessing a clinically dead person’s return of spontaneous circulation (ROSC) immediately after being administered a shock. As we have learned, a successful resuscitation is not just based on a “miracle” moment. It is a function of a community that has spent considerable time and effort to strengthen the links in the chain of survival. 

I learned many years ago that for the best trained EMTs to have the best odds for ROSC, the community should have a large number of citizens trained in the skills of CPR and be comfortable using the easily accessible nearby AED. Plenty of great advice has been written about strengthening the links in the chain of survival in each community. We know what to do, or can easily find out, but the hard work is implementing so we do not have to rely on a “miracle” moment, rather everyone knows their role and consistently practices their role! 

Let’s review some history, statistics, and common questions and answers on AEDs.    

A Brief History of AEDs
In 1849 Ludwig and Hoffa defined the concept of fibrillation of the ventricles. In 1900, Prevost and Batelli began research on ventricular fibrillation (VF) in the dog lab. They discovered a strong electrical current can be used to defibrillate. Further research by Wiggers and Wegria helped determine the amount of current for successful “counter-shocking” of VF.  

Development of defibrillators began in the 1920s and in 1947 Beck performed the first successful human defib using internal paddles on a 14-year-old boy during chest surgery. In 1956, Zoll performed the first successful human external defib using a 15-amp AC current. In 1961, Kleiger and Lown found AC current could terminate ventricular tachycardia (VT) and demonstrated the superiority and safety of DC over AC for defibrillation.  

In 1966, ambulances with physicians in Belfast performed successful prehospital defibrillation. Then in 1969, EMTs without the presence of a physician was performed in Portland, Oregon.

In the early 1970’s, Diack, Welborn and Rullman were testing prototype AEDs. Thanks to the advanced capabilities of computer technology, these defibrillators, marketed by the Cardia Resuscitator Corporation, were developed to take and interpret the ECG and proceed to shock the patient. Prehospital trials began in 1980 in Brighton, England using the Heart Aid. In 1982, the US FDA gave approval for EMT-defibrillation clinical trials in Washington, Iowa, Minnesota and Tennessee.

These “automatic” units were soon replaced with “automated” units which recommended the shock but did not actually deliver the shock till the operator clears the patient and presses the shock button. Initially, these units were called semi-automatic units but today the term used is AED. So technically, the A in AED stands for automated and NOT automatic!

Computer technology had advanced such that the device could recognize a shockable rhythm, highly likely to be found on a pulseless patient. This advance meant that the ECG screen was not needed and the units became much smaller and lighter. In addition, since interpreting the ECG was no longer needed, the devices could be applied by EMTs, EMRs, or other responders as well as the lay public trained in the skills of CPR and use of the AED.

In the 1990s, AED use expanded to many police and first responder agencies as well as the FDA approval of lay personnel use throughout the USA.

Over the next decade there were many State and local laws enacted to provide for Good Samaritan coverage as well as requirements on where AEDs should be placed for the trained public to access them (i.e. health clubs, government buildings, swimming pools, beaches and parks, airports, sports and concert venues). In May of 2003, thanks to the advocacy of AHA and Louis Acompora Foundation (LA12.org), New York was the first State to require AEDs in the schools!

Statistics Worth Noting
In my humble opinion, the AED is probably the most studied and significant life-saving device used in prehospital care in the last 35 years! Here are just a few of the stats worth noting:

  • Sudden Cardiac Arrest is the #1 killer of student athletes in the USA. 

  • Majority of adult out-of-hospital cardiac arrests (OHCA) occur at a home or residence (71.0%).  

  • A large number of adult OHCA occur in public settings (18.2%). 

  • According to 2023 US data for adult OHCA: 

  • Survival to hospital discharge was 10.2% 

  • For EMS-treated non-traumatic OHCA:  

  • Bystander witnessed adult arrests had 15.4% survival to hospital discharge 

  • 9-1-1 responder witnessed arrests had an 18.2% survival to hospital discharge. 

  • Chance of survival while waiting for EMS during a cardiac arrest decreases by 10% every minute without CPR. 

  • Immediate CPR and use of an AED can double, or even triple, survival rates. 

  • Of people in cardiac arrest who receive a shock from an AED in the first minute, 9 out of 10 live.  

  • Bystanders administer CPR about 40% of the time and AEDs even less so. This is an area where training the public in your community can make a big difference! 

Common AED Questions and Answers
Q: What is an AED and what does it do?
A:  An AED is an “automated external defibrillator.” Today’s units are lightweight, portable, and easily operated by those with limited training. They have simple voice commands for the operator to apply electrode pads to the victim’s chest so the AED can analyze the heart rhythm. The AED will advise CPR if there is no shockable rhythm. If there is a shockable rhythm the AED will advise not to touch the patient and press the shock button and then advise to resume CPR.

Q: Why is the use of an AED important to use in conjunction with CPR?
A: If the patient is in cardiac arrest cardiac chest compressions must begin right away. This will help to circulate blood to the brain, heart and lungs and buy a few moments. The cardiac rhythm must be analyzed to determine if the patient has a shockable rhythm such as VF or pulseless VT. If a shockable rhythm is found the AED will prompt the operator to deliver a shock.  Chances of survival decrease about 10% for each minute that goes by without CPR and defibrillation.

Q: Does the AED “jump start” the heart?
A:  Actually, in combination with quality chest compressions, the AED delivers a shock to the patient in VF or pulseless VT. The shock momentarily “stops” the heart’s lethal rhythm so that the heart’s pacemaker can take back over with a normal heart rhythm that is able to provide circulation.

Q: Who can use an AED?
A: Anyone who has been trained in CPR and oriented to the simple operation of an AED. This training to save a life takes very little time but is very, very important.

Q: How do you know it's the right time to use an AED?
A: The victim is found to be unresponsive; CPR has been initiated. Assure 9-1-1 has been alerted and send someone to get the AED. As soon as the AED arrives use it. Do not wait for police or fire or EMS responders to arrive on the scene to use the AED.

Q: Can I be shocked if I use an AED correctly?
A: If you use the device as the voice prompts instruct on a patient in cardiac arrest you will not be shocked. The AED will analyze and charge up if a shockable rhythm is found but you are the one who clears the patient and then presses the button to actually deliver the shock.

Q: Will I harm a person if I use an AED on someone who doesn't need it?
A: If the patient is found unresponsive and the AED is applied and recommends a shock you will not harm the patient. If a shock is delivered CPR should be started unless the patient becomes responsive. Then assess their ability to breathe and alert the EMS responders.

Q: Can a young person use an AED?
A: Yes, if trained in CPR and the simple operation of the AED. Most schools have public access AEDs and do training in their use.  

Q: If I call an ambulance, should I wait for it to arrive or use an AED in the meantime?
A: Once again, follow your training in CPR and the use of the AED. Make sure 9-1-1 has been called and if there is an extra helper have them meet the responders to help them find your location quickly. If you feel you need some extra encouragement when calling the 9-1-1 dispatcher leave the phone on speaker and they should be able to talk you through the treatment.  

Q: Who should consider owning their own AED?
A: The resuscitation guidelines do not endorse routine home AED installation due to insufficient evidence of benefit. However specific patients or their family may want to discuss this question with their physician based on their medical history. If their physician thinks it would be appropriate, in addition to family training in CPR, they can write a prescription to purchase an AED. That does not mean it will be covered by health insurance. Some states have a law making a portion of the AED costs a tax deduction so check with your accountant on this one.

Q: How much does an AED cost?
A: At ECSI we do not recommend one device over another. The AED you use should be simple, easy to use and FDA approved. The costs depend on the brand and type of use expected (i.e.: home, business, first responder agency). Don’t forget a set of replacement PADs (which have a shelf life) and the battery will need to be replaced in a few years. Estimate approximately $2000. To $3000. 

Q: Can an AED be used on a child?
A: The guidelines call for standard AED use on patients over 8 years old. For a child 1 to 8 years old pediatric pads are used which are designed to decrease the dose of the shock (pediatric-attenuated pads).  

Q: In 2024, the Cardiomyopathy Health Education, Awareness, and Research, and AED Training in the Schools (HEARTS) Act was signed by President Biden. What was the purpose of the law and how can this help schools in your community?
A: Thanks to the Smart Hearts Coalition, the AHA You’re the Cure network, Chasing M’s Foundation, and advocates like Damar Hamlin, the HEARTS Act is now the law. 

The law established a series of programs and requirements relating to cardiomyopathy. Specifically, the Department of Health and Human Services must disseminate information about cardiomyopathy and the use of AEDs to certain school professionals, families, and others, and it must develop specified risk assessment tools for cardiomyopathy. In addition, the CDC must report on certain research and surveillance activities, and the National Institutes of Health must report on its research relating to cardiomyopathy.  

The law also establishes a grant program to provide CPR training and AEDs in public schools. 

As I see it…for what it’s worth!
Advocacy for laws requiring AEDs and CPR training in our schools, at sports events and large public gatherings has been definitely worthwhile. In retrospect, rather than taking the “this type of public building and that type of public building (i.e.: gyms and health clubs and government offices) approach,” if we were starting over, I think it would have made more sense to place the AED requirement in the uniform building codes (where fire extinguishers and appropriate signage are required).

Clearly, AEDs properly placed, managed and both emergency services providers as well as the general public trained in CPR can strengthen the chain of survival and save lives. 

If you and your entire family do not know how to do CPR and how to use the AEDs throughout your community it is high time to learn how. If you are not sure how to accomplish this contact your local rescue squad or fire department for the location of their next CPR and AED training.

CPR and AED Training Organizations
Aside from your local Rescue Squad, Fire Department, hospital or community college, there are many organizations where you can learn more about CPR and AED training. Here are just a few: 

Summary
In summary, consider a few important lessons we have learned about AEDs along the way: 

  • Just because a law requires the AED has to be in places in a public venue/building does not simply save lives. Some organizations have locked the AED in an office where it may not be easily accessible when needed. 

  • Just as important as having the AED is having someone who takes the responsibility for checking the AED and its contents on a regular basis. 

  • Even though AEDs are simple to use by following the voice prompts, providers should be trained in the skills of CPR as well as how to apply and use the AED in your office. 

  • Signage counts when seconds count. Make the AED placements very obvious! 

  • Learn CPR and remember that situational awareness not only includes safety risks but also the location of the nearest AED!

References/Resources:

  • Martin SS, Aday AW, Allen NB, et al; on behalf of the American Heart Association Council on Epidemiology and Prevention Statistics Committee and Stroke Statistics Committee. 2025 Heart disease and stroke statistics: a report of US and global data from the American Heart Association. Circulation. Published online January 27, 2025. 

About the author
Bob Elling, MPA, Paramedic (retired) – has been a career paramedic, educator, author, and EMS advocate for 5 decades. He was a paramedic with the Town of Colonie EMS Department, Albany Times Union Center, and Whiteface Mountain Medical Services. He was also an Albany Medical Center Clinical Instructor at the HVCC Paramedic Program. Bob served as AHA National/Regional Faculty and participated in many successful life-saving legislative campaigns with the You’re the Cure Network. He also served as paramedic and lieutenant for New York City EMS, a paramedic program director, and associate director of New York State EMS Bureau. He has authored hundreds of articles, videos, Blogs, and textbooks to prepare EMS providers for their career. Bob is the ECSI Medical Editor for the CPR and First Aid Series, Co-Author of EVOS-2, and Co-Lead Editor of Nancy Caroline’s Emergency Care in the Streets.

Standard First Aid, CPR, and AED Eighth Edition

Standard First Aid, CPR, and AED, Eighth Edition is ideal for use within training courses designed to certify individuals in first aid, CPR, and AED. This student manual is the center of an integrated teaching and learning system that offers many resources to better support instructors and prepare students to learn life-saving skills.

Request More Information
Standard First Aid, CPR, and AED Eighth Edition

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