Pediatric Terrorism and Disaster Preparedness: A ... - PHE Home

Head injury is common in children. The head is a larger, heavier portion of a child’s body
compared with the head of an adult. It accounts for a larger percentage of body surface
area (BSA) than it does in adults, and it is a major source of heat loss. It is supported by a
short neck that lacks well-developed musculature. The calvarium is thin and vulnerable to
penetrating injury, thus allowing greater transmission of force to the growing brain of a
child. The brain doubles in size in the first 6 months of life and achieves 80% of its adult
size by age 2. During childhood, there is ongoing brain myelinization, synapse formation,
dendritic arborization, and increasing neuronal plasticity and biochemical changes. Injury
to the developing brain can affect or arrest these processes, resulting in permanent
changes.
The mediastinum is very mobile in children. Subsequently, a tension pneumothorax can
quickly become life-threatening when the mediastinum is forced to the opposite side,
compromising venous return and cardiac function.
The thoracic cage of a child does not provide as much protection of upper abdominal
organs as that of an adult. Hepatic or splenic injuries from blunt trauma can go
unrecognized and result in significant blood loss leading to hypovolemic shock.
The airway differs between children and adults. The tongue is relatively large compared
with the oropharynx, which creates the potential for obstruction of a poorly controlled
airway. The larynx is higher and more anterior in the neck, and the vocal cords are at a
more anterocaudal angle. The epiglottis is omega-shaped and soft. The narrowest portion
of the airway is the cricoid ring, not the vocal cords as in adults. Airway differences
combine to make the child’s airway more difficult to maintain as well as to intubate. The
short length of the trachea increases the risk of a right mainstem bronchus intubation. The
lungs are smaller and subject to barotraumas, resulting in pneumothorax with
inappropriate ventilation.
The BSA to mass ratio is highest at birth and gradually diminishes as the child matures.
The distribution of BSA also differs between children and adults. Children have a higher
percentage of BSA devoted to the head relative to the lower extremities. This should be
taken into account when determining the percentage of BSA involved in burn injuries and
in treating or preventing hypothermia.
The higher BSA to mass ratio also leads to more rapid absorption and systemic effects
from toxins that are absorbed through thinner, less keratinized, highly permeable skin.
Physiologic Differences
Children differ physiologically in many ways from adults. They can compensate and
maintain heart rate during the early phases of hypovolemic shock; this false impression of
normalcy can lead to administration of too little fluid during resuscitation. This can be
followed by a precipitous deterioration with little warning.
Vital signs, including heart rate, respiratory rate, and blood pressure, vary with age.
Caregivers should be able to quickly interpret whether a child’s vital signs are normal or
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