4 Traumatic Brain Injury

Assess severity with the GCS

Assessment considers the injury mechanism, vital signs, serial neurologic examinations, and Glasgow Coma Scale (GCS) components. The GCS records eye, verbal, and motor responses, and a trend in scores can be as important as one score.

For example, eye opening to speech scores $3$, verbal response with inappropriate words scores $3$, and withdrawal from pain scores $4$. Together, these responses give a GCS of $10$. A GCS from $9$ to $12$ is commonly categorized as moderate TBI; scores from $3$ to $8$ are categorized as severe, and scores from $13$ to $15$ as mild. Interpret the score alongside the full examination and clinical context.

Recognize deterioration and danger signs

A worsening examination is an emergency. Increasing drowsiness and a declining GCS—for example, a change from $14$ to $11$—should be treated as neurologic deterioration, not dismissed as ordinary sleepiness.

Promptly reassess airway, breathing, circulation, pupils, and GCS; notify the responsible emergency or trauma team; and prepare for urgent evaluation and imaging as directed. A falling level of consciousness may indicate expanding intracranial bleeding, swelling, or another evolving injury.

Danger signs after head injury include worsening headache, repeated vomiting, increasing confusion, unequal pupils, seizures, and reduced ability to awaken. Slurred speech or difficulty waking after discharge also requires immediate emergency care; call 911 if the person is difficult to awaken or rapidly worsening.

Prioritize early stabilization

For suspected severe TBI, follow trauma priorities: protect the cervical spine while addressing airway and oxygenation, support ventilation as needed, and assess and support circulation while urgently activating the appropriate trauma response.

Hypoxia and hypotension can worsen secondary brain injury. Stabilization takes priority over a detailed neurologic examination or nonurgent imaging.

Use decision support and interpret ICP

For a stable adult with minor blunt head injury, a validated decision rule such as the Canadian CT Head Rule can help clinicians decide whether CT is indicated. First confirm the patient fits the rule’s inclusion criteria and has no exclusion that makes the rule inappropriate.

Decision tools support, but do not replace, clinical judgment. Do not apply them indiscriminately outside their intended population or use them to delay care for an unstable or deteriorating patient.

For severe TBI, intracranial pressure (ICP) readings above $22\,\text{mm Hg}$ warrant prompt clinical attention and management according to the patient’s condition and the treating team’s protocol. The Brain Trauma Foundation recommends treating ICP above $22\,\text{mm Hg}$, because sustained values above this level are associated with increased mortality. Consider the measurement together with the neurologic examination and imaging, not by itself.

Avoid harmful routine treatments

Prolonged prophylactic hyperventilation is not recommended as a routine strategy to prevent ICP elevation in severe TBI. Ventilation changes that lower carbon dioxide may be considered in specific circumstances, but should not be used routinely or without careful monitoring. Excessive or prolonged hyperventilation can reduce cerebral blood flow and risk worsening brain ischemia; follow specialist guidance and local protocols.

Do not give high-dose methylprednisolone to reduce ICP after severe TBI. It is contraindicated in severe TBI and has been associated with increased mortality; steroids are not recommended to improve outcome or reduce ICP.

Plan discharge and follow-up

Discharge teaching after mild TBI should explain which danger signs require immediate emergency care and how to arrange follow-up and a gradual return to activity. Provide clinician guidance about work, school, driving, and sports as relevant.

Symptoms can change during recovery, and a dangerous complication may appear or worsen after the initial injury. Patients and caregivers should know what to watch for and how to obtain follow-up care.