Automated External Defibrillator (AED) pads are specialized adhesive electrodes that sense the heart’s electrical activity and deliver a controlled electrical shock if a life-threatening rhythm is detected in a person experiencing sudden cardiac arrest. Quick and accurate application is paramount, as the effectiveness of defibrillation decreases rapidly with every passing minute. Proper placement ensures the electrical current travels directly through the heart muscle, maximizing the chance of restoring a normal rhythm.
Essential Preparation Before Application
Before the pads can be placed, the patient’s chest must be completely bare to ensure optimal contact with the skin. All clothing, including bras and undergarments, must be quickly removed or cut away to expose the entire chest area. Any metallic jewelry or body piercings near the application sites should also be removed, as metal can interfere with the electrical current and potentially cause burns.
The skin surface must be dry for the pads to adhere firmly and for the electrical current to conduct. If the patient’s chest is wet from sweat or rain, it should be wiped dry immediately with a towel or cloth. Excessive chest hair can prevent the pads from sticking properly, which will compromise the delivery of the shock. In such cases, the area where the pads will be placed should be quickly shaved or the pads should be forcefully ripped off once to remove the hair.
Adult Pad Placement Guide
The standard application method for adults uses an anterior-lateral placement to create a clear electrical path across the heart. One pad should be placed on the upper right side of the patient’s chest, specifically just below the collarbone and to the right of the breastbone. This position is high on the chest wall, avoiding the bone structure as much as possible.
The second pad is positioned on the lower left side of the chest, situated below the left nipple and along the mid-axillary line, roughly under the armpit. This placement ensures the heart lies directly in the pathway of the electrical current flowing between the two electrodes. This maximizes the amount of cardiac tissue depolarized by the shock, increasing the likelihood of successful defibrillation. The anterior-lateral configuration also helps avoid placing pads over implanted medical devices like pacemakers.
Pediatric Pad Placement Guide
For children typically under eight years old or weighing less than 55 pounds, specialized pediatric pads or a pediatric key/switch must be used. These pads contain a dose attenuator that lowers the electrical output, preventing the delivery of an adult-sized shock which could be harmful. The placement strategy for children is distinct from adults and is known as the anterior-posterior method.
This placement involves securing one pad on the center of the child’s chest (anterior position). The second pad is placed on the child’s back, centered between the shoulder blades (posterior position). This front-and-back configuration is necessary because it ensures the pads do not touch each other on the child’s smaller torso. If the pads were to overlap, the electrical current would bypass the heart and flow directly between them, rendering the shock ineffective.
Troubleshooting and Ensuring Connection
Once the pads are firmly adhered to the patient’s bare skin, the electrode cable must be securely plugged into the corresponding port on the AED unit. The device will typically prompt the rescuer with voice commands to complete this final connection step. After the connection is made, the AED will immediately begin to analyze the patient’s heart rhythm.
If the AED displays a “Check Electrodes” or “Error” message, it indicates a poor connection between the pads and the skin. The rescuer should immediately stop compressions and press down firmly on both pads to improve contact. If the error persists, check the cable connection to the AED, and if necessary, replace the pads with a fresh set. Before the AED analyzes the rhythm or delivers an advised shock, the rescuer must verbally warn everyone to move away by shouting “Clear!” to ensure no one is touching the patient.