An automated external defibrillator (AED) is a portable device designed to treat sudden cardiac arrest, where the heart unexpectedly stops beating. This life-saving equipment delivers a controlled electrical shock to restore a normal heart rhythm. For an AED to be effective, precise pad placement is important. This guide focuses on the proper anterolateral placement of AED pads for adults and children aged 8 years and older.
Understanding Anterolateral Placement
Anterolateral placement refers to positioning AED pads on the front and side of the chest. This is the standard and most frequently recommended method for adults and children over the age of eight. This arrangement creates an optimal pathway for the electrical current to pass directly through the heart muscle. Defibrillation delivers an electrical shock to temporarily depolarize the heart muscle, allowing its natural pacemaker to re-establish a normal rhythm. Efficient current flow through the heart is crucial for successful defibrillation.
Step-by-Step Pad Application
Proper application of AED pads begins with preparing the individual’s chest. Ensure the chest is bare and dry, which may involve removing clothing or wiping away moisture.
The first AED pad should be placed on the upper right side of the chest, just below the collarbone and to the right of the breastbone. This establishes the entry point for the electrical current.
The second AED pad is positioned on the lower left side of the chest, below the left armpit, lateral to the breast, and below the nipple line. This placement allows the electrical current to effectively traverse the heart between the two pads. Once both pads are firmly in place, connect them to the AED unit, which will then guide the rescuer through the next steps.
Special Considerations for Placement
Addressing specific patient conditions helps ensure the AED functions effectively.
Excessive chest hair can prevent pads from adhering properly, which may reduce shock effectiveness. If a razor is available, shaving the area where the pads will be placed can create better contact. Alternatively, one set of pads can be applied and quickly ripped off to remove some hair, followed by the application of a new set of pads.
Individuals with pacemakers or implantable cardioverter-defibrillators (ICDs) require careful pad placement. Position AED pads at least one inch (2.5 cm) away from any visible bulges or scars indicating an implanted device. This distance helps prevent interference with the device and ensures the electrical current is directed through the heart. While pacemakers can withstand AED shocks, avoiding direct placement over them is recommended.
Medication patches, such as those for nitroglycerin or nicotine, should be removed from the pad placement area. These patches can block energy transfer and may cause skin burns. After removal, wipe the skin clean before applying pads.
Metallic jewelry generally does not interfere with AED operation unless directly under a pad. If jewelry is in the path of a pad, remove it or place the pad at least one inch away to prevent potential burns or electrical arcing.
Ensuring Proper Pad Contact and Adhesion
Achieving firm pad-to-skin contact is important for effective defibrillation. Poor contact can lead to electrical arcing, where current travels across the skin surface rather than through the heart, making the shock less effective.
Good adhesion reduces transthoracic impedance, the resistance to electrical current flow through the chest. Lower impedance allows more effective current delivery to the heart, increasing the chances of restoring a normal rhythm. To maximize adhesion and ensure optimal conductivity, press firmly on the entire surface of each pad after placement. Smoothing out any air bubbles beneath the pads further enhances contact and helps prevent issues during shock delivery.