Chapter 23: Head Trauma

High-Yield Facts

• The most common cause of head injury in children is falls. More severe injuries are caused by motor vehicle collisions, bicycle crashes, and assaults, including child abuse.

• Children with severe injuries, including those with altered mental status, focal neurologic deficits, or penetrating injuries, should undergo emergent computed tomography (CT) of the head and prompt neurosurgical consultation.

• Prevention of hypoxia, ischemia, and increased intracranial pressure is essential for children with severe head injuries.

Traumatic brain injury is a significant cause of pediatric morbidity and mortality in the United States. More than 6000 children die each year as a result of traumatic brain injury, whereas another 60,000 are hospitalized, and an additional 630,000 seek care in emergency departments.¹ Among children who die from trauma, 90% have an associated brain injury.² Hospitalization rates for mild traumatic brain injury have decreased significantly in the past 20 years, whereas rates for moderate and severe injuries are relatively unchanged.³ Pediatric brain injury leads to major morbidity from physical disability, seizures, and developmental delay. The most common cause of head injury in children is falls; however, severe injuries are more likely caused by motor vehicle collisions (with the child as occupant or pedestrian), bicycle collisions, and assaults, including child abuse, especially in the youngest children.^1,4 Boys are injured more commonly than girls, and in particular, boys aged 0 to 4 years have the highest rates of head injury–related emergency department visits compared with all other age groups.¹

Pathophysiology

Primary brain injury occurs as a result of direct mechanical damage inflicted during the traumatic event. Secondary injuries occur from metabolic events such as hypoxia, ischemia, or increased intracranial pressure. The prognosis for recovery depends on the severity of the injuries. Anatomic features, specific injuries, and intracranial pressure physiology are important components in the pathophysiology of pediatric brain injury.

Anatomy

The scalp is the outermost structure of the head and adjacent to the galea (Fig. 23-1). Beneath the galea is the subgaleal compartment where large hematomas may form, especially in infants and young children. The outer and inner tables of the skull are separated by the diploic space. The thin, fibrous dura is next, and it contains few blood vessels compared with the underlying leptomeninges, the arachnoid, and pia. Small veins bridge the subdural space and drain into the dural sinuses. Dural attachments partially compartmentalize the brain. In the midline, the falx cerebri divides the right and left hemispheres of the brain. The tentorium divides the anterior and middle fossa from the posterior fossa, with an opening for the brain stem. Cerebrospinal fluid surrounds the brain within the subarachnoid space.

The outer structures protect the brain during everyday movements and ...