In emergency care, particularly with Cardiopulmonary Resuscitation (CPR) and Automated External Defibrillator (AED) use, standardized age definitions are necessary. Physiological differences across the human lifespan necessitate different approaches to resuscitation. Treating a child with adult techniques can reduce the effectiveness of life-saving measures or cause injury due to the mismatch in body size and development. Major certifying bodies, such as the American Heart Association (AHA), establish clear boundaries to guide rescuers in making accurate decisions. These guidelines ensure that the correct compression depth, ventilation volume, and electrical energy dose are applied, tailored to the patient’s physical needs.
The Defining Characteristics of a Child
The “child” category for CPR and AED care is defined by a specific age range and physical maturity level, which dictate the appropriate response protocol. According to major resuscitation guidelines, a person is considered a child from the age of one year up to the onset of puberty. This definition relies on the combination of age and a lack of secondary sexual characteristics. For teaching purposes, puberty is often identified by the presence of axillary (underarm) hair in males or breast development in females.
The rationale for this classification is rooted in the developing body’s physiology. Children have smaller, more pliable chest walls and developing organs, meaning they cannot tolerate the same compressive force used on adults. Pediatric cardiac arrests are most frequently caused by respiratory failure, such as from choking or severe infection, rather than a primary heart problem. This difference means that rescue breaths and proper ventilation are more important for children than they are for adults in cardiac arrest.
The guidelines specify that chest compressions for a child should depress the chest by approximately two inches, or about one-third of the chest’s anterior-posterior diameter. This is a shallower depth than the adult recommendation, reflecting the need to effectively circulate blood. The use of one or two hands for compressions is also adjusted based on the child’s specific size, ensuring the proper depth is achieved.
The Infant Category (Under One Year)
The definition of a child begins where the definition of an infant ends, at the patient’s first birthday. The “Infant” category covers newborns up to 12 months of age, and this group requires specialized protocols. Infants have unique anatomical and physiological characteristics that demand specialized resuscitation techniques.
Their airways are proportionately smaller and more susceptible to collapse, and their chest walls are significantly more pliable than those of a child or adult. Because of their size, chest compressions on an infant must be delivered using a two-finger technique for a single rescuer or the two thumb-encircling hands technique for two rescuers. The recommended compression depth is about 1.5 inches, or one-third of the chest diameter, which is shallower than the child protocol.
The inability of an infant to communicate distress necessitates a unique assessment approach. When checking for responsiveness, a rescuer taps the bottom of the infant’s foot rather than shaking their shoulder. The distinction between infant and child is important because the different techniques account for the rapid developmental changes that occur within the first year of life.
Determining the Switch to Adult Protocols
The upper boundary of the “Child” definition is the point at which adult CPR and AED protocols become necessary. While a strict age cutoff of eight years is sometimes used for simplicity, the physical signs of puberty dictate the transition. Once a person shows signs of puberty, their body mass and cardiovascular system require the use of adult guidelines.
Increased body size and a larger heart mean that the patient requires deeper chest compressions and a higher-energy electrical shock for defibrillation. In cases where a person is age 12 or older but shows no signs of puberty, the rescuer should generally continue to use child protocols. However, if the patient is over 55 kilograms (about 121 pounds), adult protocols are applied, regardless of the presence of puberty signs.
Practical Application: AED Settings
The distinction between a child and an adult impacts the use of an Automated External Defibrillator (AED). The energy delivered must be attenuated, or reduced, for children. This is achieved through the use of pediatric AED pads, which are smaller and contain a built-in attenuator that lowers the energy dose to a level appropriate for the child’s size.
These pediatric pads are typically recommended for children between one and eight years of age or those weighing less than 55 pounds. If pediatric pads are unavailable, adult pads can be used, but the pediatric setting, if available on the device, should be selected. For smaller children, pads may need to be placed with one on the chest and one on the back to ensure they do not touch, which could short-circuit the electrical current.