Defibrillators deliver an electrical shock to the heart, interrupting abnormal rhythms like ventricular fibrillation to allow the heart to reset. Precise pad placement is important; incorrect placement can reduce the effectiveness of the electrical current.
Standard Adult Pad Placement
The standard method for placing defibrillator pads on adults is the anterior-lateral position. This placement ensures the electrical current effectively traverses the heart muscle. One pad is positioned on the upper right side of the chest, below the collarbone and to the right of the sternum.
The second pad is placed on the lower left side of the chest, typically below the left armpit or nipple. For female patients, this pad should be placed under the breast tissue for proper contact. This anterior-lateral configuration creates a pathway for the electrical current to pass directly through the heart, maximizing the chances of successful defibrillation.
Alternative Adult Pad Placements
While the anterior-lateral placement is standard, alternative positions for defibrillator pads may be necessary in certain situations. The anterior-posterior placement involves placing one pad on the front of the chest and the other on the back. The front pad is placed over the cardiac apex, between the midline of the chest and the left nipple. The back pad is positioned on the left side of the spine, just below the shoulder blade. This configuration is often chosen when the standard anterior-lateral placement is obstructed.
This alternative method is useful in cases where large breasts impede pad adhesion or when implanted medical devices are present on the chest. Shifting the pads slightly to avoid direct contact with scars or other medical equipment is important, maintaining a clear pathway for the electrical current through the heart.
Preparation Before Pad Placement
Before applying defibrillator pads, several steps are important for safety and effectiveness. Confirm the environment is safe to prevent accidental electrical conduction to bystanders.
Skin preparation is important for pad adhesion and electrical conductivity. The patient’s chest should be clean, dry, and as hairless as possible. If the chest is wet, quickly drying the area where the pads will be placed is important to facilitate proper contact and minimize impedance. Excessive chest hair can create a barrier, so quickly removing it with a razor, if available, from the pad placement sites is recommended to ensure good skin contact.
Remove any obstructions from the areas where the pads will be applied, including jewelry, clothing, or transdermal medication patches. Medication patches must be removed as they can block the electrical current or cause skin burns during defibrillation.
Special Considerations for Pad Placement
Special considerations apply to defibrillator pad placement. For pediatric patients, specialized smaller pads with attenuated (reduced) energy levels are necessary. These pediatric pads are often placed in an anterior-posterior configuration (one on the front, one on the back between shoulder blades) to prevent them from touching due to the child’s smaller size.
When a patient has an implanted medical device, such as a pacemaker or implantable cardioverter-defibrillator (ICD), avoid placing pads directly over the device. Position the defibrillator pads at least 1 inch (2.5-3 cm) away from the implanted device to prevent damage to the device or reduced effectiveness of the shock.
Transdermal medication patches, such as those for nitroglycerin or pain relief, must be removed from the chest before applying pads. These patches can interfere with electrical conduction and may lead to skin burns. If the patient has excessive chest hair, quickly shave or trim the hair from the areas where the pads will adhere to ensure good skin contact and effective current delivery. In a wet environment, move the patient to a dry area and thoroughly dry their chest to prevent electrical arcing and ensure proper pad adhesion.