The adage that “children are not just small adults” holds true when discussing pediatric head trauma. The pediatric craniocerebral anatomy increases the child’s vulnerability to head trauma as well as protects them against worsened severity or outcome. In general, children under the age of 2 years or who are nonverbal require a higher level of suspicion for injury, as the assessment is less revealing secondary to the child’s developmental age.
The physically larger and proportionately heavier pediatric cranium, together with the increased laxity of the cervical spine, create a fulcrum leading to an increased propensity for traumatic injury of the head and cervical spine. The skull consists of eight cranial bones, which are separated by sutures until around 18–24 months. Open cranial sutures are protective against gradual increases in intracranial pressure (ICP), for example as a result of tumors or hydrocephalus increased. Rapidly expanding mass lesions, however, are not tolerated and result increased ICP. The head circumference of infants should be measured and recorded on admission and daily, as a rapidly increasing head circumference is indicative of increased ICP. Presence of bulging or firm fontanels, with infant calm and in an upright posture, can also be an indicator of increased ICP. The infant’s skull is thinner, softer, and more deformable when fractured, but heals quickly after fracture due to accelerated bone growth.
The pediatric brain is softer due to a higher water content and less myelination. The subarachnoid space is wider. The thin pediatric skull, soft brain, and large subarachnoid space allow increased movement of the brain within the skull, which makes the child more susceptible to brain injury, including extraparenchymal hemorrhage, shearing or tearing of neuronal processes, and diffuse axonal injury.
Children have a smaller intracranial space in which smaller increases in volume produce exponentially larger increases in ICP. The pediatric skull can absorb a significant impact with little external evidence of significant intracranial injury. When evaluating the head-injured child, the nurse must consider all external indications such as bruising, swelling and lacerations, as well as the mechanism of injury and the degree of neurologic deficit.
