Properly placing AED pads varies with the age and/or size of the victim. For instance, smaller pediatric pads are to be used with infants. One pad should be placed on the infant’s chest and the other pad on its back. This is known as anterior posterior placement. On an adult, AED pads should be placed on the opposing side of the chest. This is referred to as anterior lateral placement.
How to Place AED Pads
Check the scene and the victim:
Make sure they are dry and free from conductive materials that could mis-conduct the electricity from the AED. Make this check quickly, drying the body, removing chest hair if needed to ensure the pads stick and work immediately. Remove or avoid contact with pacemaker and other interfering items by at least an inch. Jewelry and other metal objects must be removed from the person’s body. Watch out for these items and materials:
- Aluminum, Steel, Iron: Used for seating and other structures, especially at sports venues.
- Sea- or Rain-water: typical of outdoor conditions.
- Moisture: From cleaning, drinks, spills, swimming, perspiration, etc.
- Gold, copper, etc: Be especially aware of upper body jewelry–nipple piercings, nose- and ear-rings, etc.
- Water on the victim’s body: Perspiration, spills, swimming or shower, etc.
The person must be lying down on a firm dry surface with working space around them so that CPR and AED deployment can be performed.
Choose the AED Pad to be Used (Adult or Pediatric)
Attach the AED Pads to the Victim (Adults & Children)
Adult Pad Placement
AEDs are typically designed for adults, delivering 150-200 Joules of electricity when giving a shock. They come with full-sized electrode pads. These adult pads are placed on opposing sides of the chest as shown below:
Image from Zoll.comThis placement of adult pads is referred to as anterior lateral placement. This means that one pad will be placed above the nipple on the victim’s right-hand side of the chest, just below the clavicle (collar bone). The other pad placement is below the victim’s left nipple. This pad is placed lower, below the left nipple, and more to the side of the chest.
Adult pads can also be placed front and back on the victim if necessary. This anterior posterior position of the defibrillator pads can be used to avoid a pacemaker, nipple piercings, wounds, etc.
Image from Zoll.comPediatric Pad Placement
If a child is under the age of eight, weighing less than 55 lbs, pediatric pads should be used for defibrillation. These pads are usually smaller, making it easier to fit them to the child’s torso. They are also designed to attenuate (reduce) the amount of electrical energy to 50 Joules of power. This reduction in power is accomplished either through the size and wiring of the pads themselves, or by the use of a switch or key on the AED machine.
When placing AED pads on a child or infant, the first pad goes on the front, just to the victim’s left-center chest. The second pad goes on the child/infant’s back, exactly between the shoulder blades, as shown above.
For pediatric defibrillation, the anterior posterior position of the pads is used. This is to adjust for the difficulty in placing both AED pads in a small area. This way the electrical pathway can reach the heart without danger of short circuit while still making contact with a sufficient area of bare skin.
Image from Zoll.comIf not already attached to the machine, plug the pads into the AED case after they have been attached to the victim’s body.
NOTE: In the relatively uncommon event of a child or infant SCA, there may not be a pediatric-equipped AED available. If this is the case, the rescuer should use an adult AED. The choice to go without attempting defibrillation is untenable, since Sudden Cardiac Arrest virtually always results in death.
Follow the Instructions from the AED.
Once each AED pad is securely in place according to proper aed pad placement, follow the instructions given by the AED, whether it be to continue CPR, move back from the patient, press the shock button, etc. If the AED stops giving direction, continue CPR until the emergency medical services team arrives.
You can learn more about AEDs, the cardiac “Chain of Survival”, and how to get trained on CPR and AED use below.
What is an AED?
An AED is the essential instrument for use in reviving a Sudden Cardiac Arrest (SCA) victim. An SCA victim has no pulse, is not breathing, loses consciousness, and will most always die within minutes if not given first aid according to the SCA “Chain of Survival”.
The Chain of Survival–CPR and AED
The “Chain of Survival”, as shown in the diagram above, indicates that both CPR and deployment of an AED (automated external defibrillator) are to be used in order to save the life of a person who has collapsed due to Sudden Cardiac Arrest. Even when a person is given CPR, deployment of an AED is virtually the only hope of reviving someone who has succumbed to SCA (sudden cardiac arrest–fibrillation of the heart brought on due to stress, heart disease, or accident, typically electrocution) in an out-of hospital setting.
Development of the AED
In the last century, since the discovery in the 1930’s and 1940’s that an electrical shock could restore a normal heart beat, AEDs have become increasingly more sophisticated. The term AED, which stands for “Automated External Defibrillator”, means that an AED machine works largely on its own and also uses electrode pads which are applied externally to the victim’s chest. These electrode pads are developmental descendants of electric paddles that were first used in open-heart surgery.
Electricity in the Human Body
Electricity isn’t just in the wires of a house, automobile, or street light, etc; it is everywhere, even in the human body, where it is the force behind all of our body functions. Our cells are specialized to create and conduct electrical currents. The elements in our bodies, like sodium, potassium, calcium, and magnesium, have a specific electrical charge.
Nearly all of our cells can use these charged elements, called ions, to generate electricity. This electrochemical force is required for the nervous system to send signals throughout the body, to and from the brain.
Electricity in the Heart
More to the point regarding giving an AED shock to an SCA victim is the way electricity works in the heart. In order for the heart to pump, cells must generate electrical currents that allow the heart muscle to contract at the right time. Doctors can even observe these electrical pulses in the heart using a machine called an electrocardiogram or ECG. It is electricity that makes it possible for our hearts to beat continuously while we go through our daily routines–moving, thinking, feeling–and those electrical impulses continue to keep it pumping while we sleep.
A pacemaker region, the sinus node, is located in the heart’s right atrium. It is the control center for the heart. In this region a spontaneous electrical impulse is created by the diffusion of calcium ions, sodium ions, and potassium ions across the cell membranes to produce a normal heart rhythm.
When SCA occurs, a disruption in the heart’s electrical currents leads to immediate collapse–the heart ceases its regular beat, breathing stops, and the victim loses consciousness. When the heart begins a particular arrhythmia, called ventricular fibrillation, a sufferer’s life is in danger and CPR and AED must begin immediately if the person is to survive.
AEDs Operable by Lay Bystanders
The AEDs external function, using electrode pads which are applied externally to the victim’s chest, makes these medical machines operable by lay persons in any out-of hospital circumstances. Thus, chances of successful rescue in this life-or-death emergency are greatly improved.
Today’s AED machines, though sophisticated in their design, have an increasingly friendly user interface with visual media and auditory cues. As soon as the AED is opened and/or switched on, it begins to guide the user in its deployment, with automatic audio playing while visuals are shown. In addition to guided defibrillation, AED devices now even include real-time guidance for high-quality CPR. With sound and pictures, CPR hand position and compression rates are indicated, correct AED pad placement is shown, etc.
Training for CPR and AED
Knowing that today’s AEDs are very easy to use raises our confidence when it comes to attempting an SCA rescue; nevertheless, rescuers want to have as much first-aid knowledge and skill as they can, with as few limitations as possible. Since CPR and AED use are at the core of the “Chain of Survival”, it is in these areas where specific knowledge and training are most beneficial.
Learn Best Practices
Study and coursework in CPR and AED are highly encouraged. In these courses, emergency simulations give supervised training so that the first-aider has actual “hands-on” experience in giving highly effective CPR. More to the point of this article, deploying an AED is practiced on various models, adult, child, and infant:
- Selection of AED pads (adult or infant),
- AED pad placement (anterior posterior placement, anterior lateral position),
- proper attachment of AED pads ( preparing skin, use of gel, firm pressure).
Defibrillator pad placement directly influences the effectiveness of the AED machine as it analyses the heart rhythm and delivers any needed AED shock. Learning key points regarding quick and accurate AED activation, victim preparation, and AED pad placement lead to more successful rescue outcomes.
Courses and Resources
There are many resources and opportunities available to gain skill in these life-saving techniques. There are trustworthy, cost-effective, and easy-to-find courses and materials. You can browse CPR and AED training courses on our site.
Steps to perform a Life-saving SCA Response
Recognize SCA
First in the Chain of Survival is to “Recognize SCA.” No pulse, not breathing, losing consciousness = SCA.
Call emergency services
Once SCA is recognized, as shown in the diagram above, call emergency services (911 in the USA).
Begin CPR
To keep blood moving to the brain and vital organs, CPR should be started immediately. This is also thought to prepare the heart to receive a defibrillating electric shock from an AED, if needed.
Deploy AED
Here are key points to know and steps to follow as you deploy an AED (after SCA has been recognized, 911 has been called, and another bystander has retrieved an AED while CPR has begun):
- Remember, it is the human factor of the trained first-aider that can make a rescue successful. Evaluating the scene, taking fast action in preparing the SCA victim, and efficient, precise AED pad placement make a moment-by-moment difference in the future of a person who has succumbed to SCA.
- An AED works by passing an electrical current through the body, targeting the heart for analysis and possibly one or more shocks. Understanding the electrical workings of an AED–and specifically the AED pads themselves–is the key to a successful rescue from SCA.
- Automated external defibrillator pads are constructed of thin metal plates with wires attached. These plates are placed onto a plastic shell with one side uncovered. That side is coated with an adhesive gel containing metallic particles. This gel prevents skin burns and helps the AED pads send electrical energy directly to the heart. Full pad-to-skin contact, with a thick gel layer, is essential. An AED kit often includes extra gel to put on the aed pads if needed.
- Two pads are made for an AED. One pad goes on the front chest wall, while a second pad is placed on the upper body in an opposing position, normally the side of the chest, on the left chest wall.