Complete Guide to CPR and Automated External Defibrillator

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Key Takeaway

  • The heart operates through electrical signals that alert it to pump blood.
  • V-tach and V-fib are, in most cases, rectifiable through electrical shock delivered by AED.
  • The AED analyses the state of the heart and delivers an electrical shock (defibrillation).
  • The electric shock enables the heart to restore its normal rhythm.
  • Every minute is delayed before CPR, and AED reduces the chances of survival rate by 10%.
  • Everyone must learn skills in performing CPR and how to use the AED.


Information on using the AED is essential as you never know who you'll use the skills on. Online CPR/AED certification courses are available at your convenience with no limitations and can be taken anywhere at any time. Your computer and internet connection are all required to take the CPR/AED classes.


Understanding the Heart Rhythm

The heart operates through electrical signals that alert it to pump blood. The electrical signal results in the ventricles contracting to squeeze blood out of the heart. After each contraction follows a relaxation whereby blood flows into the heart. When the heart is ailing from an injury or disease, its electrical activity is likely to disrupt.

In the event the circulation of blood through the body is insufficient. In most instances, the ventricles fibrillate or quiver in what is known as ventricle fibrillation (V-fib). The second instance is when the ventricles contract faster than usual, and it is known as ventricular tachycardia (V-tach)

The result of this is sudden cardiac arrest. The electric signals occur randomly, resulting in chaos within the heart. The limited supply of oxygen within the body causes the individual to collapse and stop breathing.


How To Use AED?

When faced with an emergency, dial-up emergency services (911) and commence CPR immediately. Rescuers should keep performing CPR until the AED is ready for use. When using the AED, you should be familiar with the manufacturer's instructions on its operation and the maintenance guidelines.


Precautions to Take When Using the AED:

  • When using the AED, do not wipe the victim's chest with alcohol, as it is highly flammable. Adult-designed AED or pads should not be used on children weighing below 55pounds or younger than eight years unless necessary. Instead, use the recommended pediatric AED pads. Pediatric-designed pads should also not be suitable for children older than eight years or over 55pouns as they deliver lower energy only suited for children.
  • Avoid touching or moving the cardiac arrest patient when the AED device is analyzed, as it may affect the results. Ensure that nothing and no one is in contact with the victim before applying shocks. The victim being shocked should not be touched during defibrillation as they can get shocked.
  • The environment should be free of flammable items such as free-flowing oxygen and gasoline.
  • AED should not be used on a moving vehicle as motion could easily affect the analysis.
  • The victim should not lie in a wet environment when the rescuer operates the defibrillator.
  • Any medical patches on the chest, such as nitroglycerine, should be removed using gloves before the shocks are applied.
  • You should not use a radio or a phone within 6feet of an AED device. In contrast, in use as it can affect radiofrequency interference, infrared interference, and electromagnetic interference affect the AED analysis.


Procedure for Using the AED Adults

There are different types of AED. However, all the devices have standard features, including voice prompts electrode pads (AED/ defibrillation pads), visual displays, or buttons.


  • Turn on the AED device.
  • Expose the victim's chest. Wipe it dry using gauze pads or a clean towel to ensure that the AED pads stick onto the victim's chest as required.
  • Peel the backing off the pads to reveal the pad's adhesive surface. Apply the pads on the victim's bare and dry chest. One pad goes to the upper right chest, while the other goes to the left side.
  • If need be, plug the connector into the AED.
  • Push the button "analyze" and let the device analyze the victim's heart rhythm. While the machine is analyzing, everyone should stay clear of the victim, and no one should be in contact as it will give incorrect results.
  • When the device indicates the need for a shock, everyone should stay aside, and no one should touch the victim, including the rescuer. Say out loudly, "everyone stand clear." Then push the shock button depending on the device you are using. Some automated AEDs will automatically deliver a shock.
  • After delivering the shock, perform CPR on the victim for about 2 minutes and progress with the AED prompts.


Stop CPR when you notice signs of life in the victim, such as breathing. Monitor the victim's condition and breathing.

Also read
What Are The Benefits of AEDs at Workplace

Procedure for Using AED for Children and Infants

Sudden cardiac arrest in children and infants results in ventricular fibrillation. The causes are not immediate and may be due to the following:

  • Sudden infant death syndrome
  • Congenital heart disease
  • A hard blow on the chest
  • Traumatic injuries such as poisoning, electrocution, drowning, and vehicle accidents
  • Breathing and airway problems


Always call the emergency medical services first. Use an AED with pediatric pads if it is available. Only use the adult-designed pads in the absence of those intended for pediatrics. Follow the local protocol and guidelines provided by the manufacturer. Ensure you follow the safety precautions as required when using the AED.


Steps To Use AED are as follows:

  • Turn on the AED.
  • Expose the infant's chest and wipe it dry.
  • Apply the pediatric AED pads on the child's chest. One pad goes to the upper right chest while the other to the left side. The pads should not be in contact with each other. If they risk touching, apply one pad in the middle of the chest and the other on the child/infant's back in the middle of the shoulder blades.
  • If necessary, plug the connector into the AED.
  • Ensure that everyone stays clear of the victim. Press the "analyze" button or let the AED analyze the heart rhythm depending on the type of device you are using.
  • If the device indicates the need for a shock, ensure that no one is in contact with the victim. State loudly, "Everyone, stand clear," then press the shock button as indicated on the device.
  • After delivering the shock to the victim, perform 2-minute CPR and follow through with the AED prompts.


Stop the CPR once you notice an indisputable sign of life, such as breathing. Instead, monitor the victim's breathing and condition.


How to Use AED in Special Situations?



Remove the victim from the water before defibrillation and ensure no water puddles around. The use of AED in water is harmful to those around them. Remove any wet clothing from the victim and wipe the chest completely dry. Seek shelter from rain and avoid getting the AED pads wet. Take the least time possible to save the victims life.


Victims with implanted pacemakers and implantable cardioverter-defibrillator

Pacemakers are implanted in people whose hearts are weak, skip beats, beat slowly, or too fast. The device is commonly implanted below the person's left collar bone and, in other cases, in other parts of the body. An implantable cardioverter (ICD) is a smaller version of the AED. When administering AED to such a victim, you should avoid placing the pads directly over the implant as it interferes with the shock delivery. However, if you are unsure if the victim has one, follow the instructions on using the AED. It is not harmful to the responder and the victim. In such cases, mild and harmless shocks can be felt by responders when giving CPR.


Medication patches

A person should remove victims with medication patches of any kind on the chest in gloves before placing the pads. Never under any circumstances should AED pads be placed on medical pads.


Victims with Hypothermia

Hypothermia occurs when the body is unable to stay warm. It could be due to prolonged exposure to cold conditions. For victims of hypothermia who are not breathing, begin CPR immediately till the AED is ready for use. Then, follow through with the standard AED procedure on the AED use, taking the necessary preventive measures such as water.


  • Avoid unnecessarily shaking the victims. It could result in ventricular fibrillation. Try warming up the victim to prevent further heat loss.


Metal surfaces

You can deliver a shock using an AED while the victim is lying on a metal surface. However, the AED pads should not come into contact with the metal surface.



Jewelry and body piercings do not interfere with AED shocks. Rescuers should, therefore, not waste time locating and removing such from the victims. However, they should take caution not to place an AED pad directly over jewelry and piercings.

It is essential to follow the instructions of the AED you are using. Read the operator's manual thoroughly to maintain the AED taking keen note of warning signs such as low battery and faulty signals.


Also read
What to Look for When Choosing a CPR Certification Course?


Cardiopulmonary Resuscitation and the use of an Automated External Defibrillator are critical in the case of a cardiac emergency. Interested persons can enroll in CPR/AED online certification classes, where AED training is available alongside CPR. The CPR/AED classes you take up could save a person's life in the future. 

Also, an online CPR/AED recertification program is available for persons with outdated certifications. AED certification renewal will allow you to refresh your skills and knowledge. It also helps keep track of the changes in the performance of CPR and the use of the AED.

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