Approach to traumatic brain injury (pediatrics): Clinical sciences

Traumatic brain injury, or TBI, refers to brain damage that results from an external mechanism, like a fall, motor vehicle accident, or non-accidental trauma. When a patient presents with traumatic brain injury, it is important to stabilize them urgently, assess the severity of the injury, and determine the need for imaging.

Now, if a pediatric patient presents with a traumatic brain injury, perform a primary survey by assessing their ABCDE. Then, stabilize the airway, breathing, and circulation; and immobilize the neck and spine. Obtain IV or intraosseous access, start IV fluids, continuously monitor vital signs, and provide supplemental oxygen, if needed.

It’s important to evaluate patients with TBI using the Glasgow Coma Scale, or GCS. This scale assesses the patient’s eye opening in addition to their motor and verbal responses, to determine their level of consciousness. The GCS provides an objective measurement to assess the degree of brain injury. For preverbal children, usually those under two years of age, a modified Pediatric GCS can be used instead.

Here’s your first clinical pearl! Any patient with a TBI can develop increased intracranial pressure, or ICP, as a result of expanding intracranial hemorrhage or cerebral edema. If it’s not recognized and treated promptly, increasing ICP can lead to brain herniation, which can further cause long-term neurologic sequelae and death.

Now, as ICP increases, it can lead to uncal herniation which can compress the oculomotor nerve. This impairs the parasympathetic function, leading to pupil dilation on the ipsilateral side. Other clinical signs of brain herniation include focal neurologic deficits and abnormal posturing. Finally, be on the lookout for Cushing triad, which consists of bradycardia; widened pulse pressure, which means there is a large difference between systolic and diastolic blood pressure; and irregular respirations known as Cheyne-Stokes breathing.

Okay, let’s go back to GCS. If the patient has a GCS score below 13, you should consider moderate or severe TBI. Next, perform a focused history and physical examination. History usually reveals a high-risk mechanism of injury, such as a fall from higher than three feet, a head impact from a high-velocity object, or a motor vehicle accident. Some patients report a worsening headache, and they may have experienced loss of consciousness, change in mental status, emesis, or seizures.

The physical exam typically demonstrates altered mental status. You may also notice signs of trauma, such as a skull defect; or indications of a basilar fracture, like raccoon eyes, or the Battle sign, which is bruising behind the ears. In some cases you might detect clear cerebrospinal fluid leaking from the nose or ears; blood behind the eardrum; facial weakness, or loss of taste, smell, or hearing. If you see any of these findings, obtain a head CT to assess for intracranial bleeding, also called hemorrhage.

Let’s first talk about conditions with hemorrhage present. Starting with epidural hematoma, this type of intracranial bleeding occurs with blunt trauma to the temporal bone, leading to fractures. Because the middle meningeal artery is close to the temporal bone, sharp bone fragments or blunt trauma itself can injure the artery and cause bleeding into the epidural space. Typically, patients present with initial loss of consciousness, then a lucid period, after which their mental status deteriorates. If imaging demonstrates a biconvex hyperdense area between the brain and the skull, that’s an epidural hematoma.

Next up is subdural hematoma. Subdural hematoma is often caused by direct head trauma or by rotational forces from vigorous shaking, as seen in abusive head trauma. In this case, blood collects within the potential space between the dura mater and arachnoid layers. If imaging reveals a crescent moon-shaped bleed in the subdural space that crosses the suture lines, your patient has a subdural hematoma.

Here’s a high-yield fact! Suspect abusive head trauma when a child under two presents with injuries inconsistent with the reported history. In addition to head trauma, these children may have rib injuries or extremity injuries as well as retinal hemorrhages or papilledema. Subdural hematomas, subarachnoid hemorrhage, and diffuse axonal injury are commonly associated with abusive head trauma.

Let’s move on to subarachnoid hemorrhage. In this case, bleeding occurs within the subarachnoid space, which is normally filled with cerebrospinal fluid or CSF. Children with subarachnoid hemorrhage typically report neck stiffness and headache. If CT reveals a hyperdense layering along the convexities of the cerebral cortex, diagnose subarachnoid hemorrhage.