Introduction
Injury is the leading cause of death and disability in children, and adolescents, young adults, and pediatric patients constitute 25% of all injured patients in the United States. While overall mortality is one-third the rate of trauma deaths in adults, case fatality rates for children are higher [1]. In other words, for equivalent trauma severity, children are more likely than adults to die during transport and resuscitation. Although prehospital encounters with pediatric patients represent a small fraction of EMS transports, traumatic injury is the most common chief complaint for EMS response in the pediatric age range [2].
Most injuries in children fall into the category of minor trauma, such as contusions and lacerations, and typically require straightforward application of the basic tenets of wound care, splinting, and immobilization. However, being prepared to manage major multisystem pediatric trauma involves a thorough understanding of the unique anatomical and physiological characteristics of the pediatric patient, as well as a working appreciation of pediatric growth and development [3,4]. The effect that these factors can bring to bear upon injury presentation and patient assessment, and thus the establishment of resuscitation and treatment priorities, is significant.
The following discussion is organized around a system-based inventory of what makes children different and an analysis of how these differences can affect the approach to the pediatric trauma patient. The clinical implications of these unique attributes are highlighted in the context of the trauma survey. Also important is a basic appreciation of injury mechanisms in children, as they differ from those in older patients. The recognition of particular injury patterns can be important clues in the field assessment and management of the pediatric trauma patient.
Anatomical and physiological considerations
There are several key anatomical and physiological characteristics unique to the pediatric patient of which the prehospital professional needs to be aware when evaluating an injured child. These characteristics can affect the presentation of traumatic injuries, especially in young children, and require a heightened index of suspicion during the trauma survey for subtle signs and symptoms of occult injury.
General
Because of a child’s smaller body size, traumatic forces can be distributed over a larger area, thus making multisystem trauma the rule rather than the exception with childhood injuries. Children often sustain internal injuries with little or no external evidence of trauma. Thus, as a general rule, internal injury cannot be ruled out in a child merely based on the absence of external signs of trauma. Children also have a large surface area to body mass ratio and are particularly vulnerable to thermoregulatory derangements from prolonged environmental exposure. Particularly in infants, the relatively large head can be a source of significant unrecognized heat loss in a trauma resuscitation situation. The simple placement of a cap on the head of an infant during transport and turning up the heat in the ambulance can help to obviate this problem.
Head
Head injury is the most common cause of serious trauma in children. The disproportionately large head in young children functions like a “lawn dart,” causing them to lead head-first during falls or rapid deceleration mechanisms, such as car crashes. More than 80% of multisystem pediatric trauma cases involve the head and nearly one-third of all childhood injury deaths result from head injury [1,4]. Among the highest priority early interventions in the management of multisystem pediatric trauma are those directed at limiting the severity of traumatic brain injury and preserving brain function.
Airway
The pediatric airway has several unique anatomical features with which the prehospital professional must be familiar to ensure successful airway management. These features are usually present until about 8 or 9 years of age when the airway assumes more of an adult configuration. Because of the relatively short neck, particularly in young children, the larynx is more cephalad and far more anterior than what would be visualized on direct laryngoscopy of an adult patient. In fact, the cricoid pressure provided by the Sellick maneuver is not only necessary to occlude the esophagus during endotracheal intubation, but is often required to actually bring the airway into view. The diameter of the pediatric airway is obviously much smaller than the adult airway and is far more vulnerable to compromise from relatively small amounts of obstructive material, blood, or edema. The tongue is a relatively larger structure within the mouth and is actually the most common cause of upper airway obstruction in the young child.
The epiglottis is a floppier, U-shaped structure that generally requires use of the straight Miller blade to control it directly and provide adequate visualization during intubation. The narrowest part of the pediatric airway is the subglottic region, below the vocal cords, as opposed to at the cords themselves. This “physiological cuff” obviates the need for cuff inflation or for cuffed endotracheal tubes altogether before 8 years of age. Children are obligatory abdominal breathers and depend on sufficient diaphragmatic excursions to ventilate properly. Swallowing air, or aerophagia, with subsequent gastric distension is common in the trauma resuscitation setting. Gastric decompression with an orogastric or nasogastric tube is required to prevent disruption of ventilatory mechanics [5,6].