An Automated External Defibrillator (AED) can be used on an infant, defined as a child under one year of age, but this procedure requires specialized equipment and careful adherence to pediatric protocols. An AED is a portable device designed to deliver an electrical shock to the heart to reset a dangerous rhythm, such as ventricular fibrillation. Because an infant’s body is significantly smaller than an adult’s, using an AED safely and effectively necessitates a reduction in the energy delivered and a change in the placement of the electrode pads. Using the proper equipment and following the correct sequence of actions ensures the electrical therapy is delivered at a safe level directly through the infant’s heart.
Understanding Infant Cardiac Arrest
The cause of cardiac arrest in infants is typically different from that seen in adults, which influences the initial steps of resuscitation. Adult cardiac arrest often results from a primary electrical malfunction, like ventricular fibrillation. In contrast, infant cardiac arrest is most commonly a secondary event resulting from respiratory failure or shock, meaning the heart stops due to a lack of oxygen (asphyxial cause). This is often due to severe illness, trauma, or airway obstruction.
The lack of oxygen first causes respiratory distress, leading to a slow heart rate (bradycardia) before the heart stops entirely. This physiological difference means the most immediate and impactful intervention is high-quality Cardiopulmonary Resuscitation (CPR), particularly rescue breathing, to reintroduce oxygen. Attaching the AED should not delay the delivery of high-quality compressions and ventilations.
Essential Pediatric AED Equipment and Setup
Using an AED on an infant requires specialized accessories to ensure the electrical shock is safe for a small body. The primary difference is the use of pediatric attenuated pads, which reduce the energy dose delivered by the AED. Standard adult pads deliver a high energy level (often 150-200+ Joules), which is too much for an infant and could damage the heart muscle. Pediatric pads automatically lower this energy, typically to a safer range of about 50 Joules. This reduction is achieved either by the pad’s internal wiring or by a special key or switch on the AED unit that activates the pediatric mode.
The physical placement of the pads is also modified to ensure the electrical current passes effectively through the heart without the pads touching each other. The recommended method is the anterior-posterior placement: one pad is placed on the center of the sternum, and the second pad is placed directly on the infant’s back, between the shoulder blades. This configuration is preferred because an infant’s small chest size makes the standard adult anterior-lateral placement difficult. If pediatric pads are unavailable, adult pads can be used as a last resort, but the anterior-posterior placement is mandatory to prevent the larger pads from touching.
Using the AED: Step-by-Step Protocol
The protocol for using an AED on an infant must integrate seamlessly with high-quality CPR efforts. If a rescuer is alone, they should perform about two minutes of CPR before pausing to call emergency services and retrieve the AED. Once the AED arrives, it should be turned on immediately, and the rescuer should follow the device’s voice prompts. The infant’s chest must be exposed, and if wet, the skin should be quickly dried before applying the pads.
The pads must be firmly applied to the bare skin in the anterior-posterior position. After plugging the pads’ connector into the AED unit, ensure no one is touching the infant while the device analyzes the heart rhythm. If the AED determines a shockable rhythm is present, the device will advise a shock; the rescuer must loudly announce “clear” and then press the shock button. Following the shock, the rescuer must immediately resume two minutes of high-quality CPR, starting with chest compressions. This cycle continues until the infant shows obvious signs of life, emergency medical services take over, or the AED advises a re-analysis.