Automated External Defibrillators (AEDs) are publicly accessible devices designed to deliver an electrical shock to treat sudden cardiac arrest (SCA). While AEDs are effective for adults, pediatric SCA often arises from different underlying causes, requiring adjustments to the standard adult treatment protocol. Applying defibrillation to a young patient without proper modifications can deliver excessive energy, potentially harming the smaller heart muscle. Specialized guidelines ensure this intervention is delivered safely and effectively for infants and children experiencing cardiac arrest.
Defining Infant and Child Age Ranges
A clear distinction between age and weight categories determines whether a patient requires specialized pediatric defibrillation settings. The term “infant” applies to a child younger than one year of age. The “child” category includes patients from one year of age up to the age of puberty, or those weighing less than 55 pounds (25 kilograms).
If the patient shows signs of puberty, such as breast development in females or axillary hair in males, they should be treated using adult protocols, regardless of chronological age. The adult protocol applies to anyone 8 years of age or older, or those who weigh more than 55 pounds. This delineation helps rescuers quickly determine the appropriate pads and energy dose for the patient’s body size.
Using Pediatric Attenuator Pads
The primary specialized equipment for younger patients is the pediatric attenuator system, which modifies the energy delivered by a standard AED. These specialized pads or keys reduce the electrical current from the adult level. The attenuator decreases the energy output from the defibrillator to a dose suitable for a child, typically falling within the range of 50 to 75 Joules. This reduction prevents the delivery of an excessive shock that could damage the smaller heart muscle.
Pad placement changes for small children to ensure the heart lies within the electrical pathway and the pads do not touch. For infants and small children, the recommended placement is anterior-posterior, with one pad on the center of the chest and the other directly on the back. This configuration prevents arcing and ensures the current crosses the heart structure. For larger children, pads may be placed in the standard adult position (one below the collarbone, one on the side under the armpit), provided they do not overlap.
In a time-sensitive emergency, if pediatric pads or a pediatric switch are unavailable, the recommendation is to use adult pads as a last resort. Using adult pads is preferred over delaying defibrillation, especially since SCA is often fatal without prompt intervention. When using adult pads on a small patient, rescuers must ensure the pads are placed on the chest and back to prevent contact and maximize the distance between them.
Primary Focus: CPR Before Defibrillation
The recommended sequence of care for pediatric cardiac arrest differs significantly from the adult protocol due to a difference in the cause of the event. In adults, SCA is frequently the result of a primary electrical problem, such as ventricular fibrillation, requiring immediate defibrillation. Conversely, cardiac arrest in infants and children is most commonly a secondary event caused by progressive respiratory failure or shock. This means the heart has stopped due to a lack of oxygen rather than an initial electrical malfunction.
Because the root cause is often a lack of oxygen, the priority is to restore breathing and provide ventilations alongside chest compressions. For an unwitnessed out-of-hospital pediatric arrest, the standard of care involves performing two minutes of high-quality cardiopulmonary resuscitation (CPR) before pausing to utilize the AED. This initial period of CPR, including rescue breaths, aims to re-oxygenate the blood and tissues before a shock is delivered.
The immediate attachment of the AED is recommended as soon as it becomes available. However, the emphasis remains on minimizing interruptions to chest compressions and effective ventilation. Initiating high-quality CPR immediately and calling emergency services are the first steps in the pediatric chain of survival.