Emergency Department Approach to Traumatic Brain Injury
All patients with suspected traumatic brain injury presenting to the emergency department require immediate assessment using the Glasgow Coma Scale (GCS), followed by risk-stratified neuroimaging and hemodynamic stabilization, with the primary goal of preventing secondary brain injury through early recognition of intracranial pathology and rapid transfer to specialized neurosurgical centers when indicated.
Initial Assessment and Triage
Severity Classification by GCS
The initial ED evaluation must immediately classify TBI severity:
- Severe TBI (GCS ≤8): Requires immediate aggressive management
- Moderate TBI (GCS 9-12): High-risk for deterioration
- Mild TBI (GCS 13-15): Comprises 70-90% of ED presentations but still requires systematic evaluation 1
Critical Vital Sign Targets for Severe TBI
Maintain systolic blood pressure >110 mmHg before measuring cerebral perfusion pressure 2. Even a single episode of hypotension (SBP <90 mmHg) significantly worsens neurological outcomes 2. Avoid hypotensive sedatives and correct hypovolemia immediately with vasopressors (phenylephrine or norepinephrine) if needed.
Neuroimaging Strategy
For Severe TBI (GCS ≤8)
Perform non-contrast head CT and cervical spine CT without delay 2. The CT scan is the reference standard for diagnosing primary brain lesions and guides neurosurgical intervention and monitoring decisions 2.
Consider CT angiography of supra-aortic and intracranial arteries in patients with risk factors for traumatic vascular dissection 2.
For Mild TBI (GCS 14-15)
Level A Recommendation: Non-contrast head CT is indicated if the patient has loss of consciousness or posttraumatic amnesia AND one or more of the following 3:
- Headache
- Vomiting
- Age >60 years
- Drug or alcohol intoxication
- Short-term memory deficits
- Physical evidence of trauma above the clavicle
- Posttraumatic seizure
- GCS <15
- Focal neurologic deficit
- Coagulopathy
Level B Recommendation: Non-contrast head CT should be considered even without loss of consciousness if 3:
- Focal neurologic deficit present
- Vomiting
- Severe headache
- Age ≥65 years
- Physical signs of basilar skull fracture
- GCS <15
- Coagulopathy
- Dangerous mechanism (ejection from vehicle, pedestrian struck, fall >3 feet or 5 stairs)
Critical caveat: Up to 15% of patients with GCS 15 will have acute lesions on CT, though <1% require neurosurgical intervention 3. The challenge is identifying which patients harbor life-threatening injuries.
Role of MRI and Biomarkers
MRI has no role in acute ED evaluation of TBI—CT remains the imaging modality of choice due to availability and speed 3.
Biomarkers (S100b, NSE, UCH-L1, GFAP) are not recommended for routine clinical use in the ED, as uncertainties remain regarding normal ranges and clinical decision thresholds 2.
Transfer and Disposition
Severe TBI
Immediately transfer to a specialized center with neurosurgical facilities 2. Management by a specialized neuro-intensive care unit significantly improves neurological outcomes and reduces mortality, even for patients not requiring neurosurgical procedures 2. Non-specialized centers must rapidly identify patients requiring transfer.
Indications for Tracheal Intubation Before Transfer
Intubate patients with 4:
- GCS ≤8
- Deteriorating consciousness (fall in GCS ≥2 points or motor score ≥1 point)
- Loss of protective airway reflexes
- Inability to maintain PaO₂ ≥13 kPa
- Hypercarbia (PaCO₂ >6 kPa)
- Spontaneous hyperventilation (PaCO₂ <4.0 kPa)
- Seizures
- Bilateral mandible fractures or copious oral bleeding
Physiological Targets During Transfer 4
- Blood pressure: SBP >110 mmHg (MAP >90 mmHg)
- PaCO₂: 4.5-5.0 kPa (30-35 mmHg initially until arterial gas available)
- Oxygenation: PaO₂ ≥13 kPa (avoid hyperoxia)
Discharge Criteria for Mild TBI
Patients with isolated mild TBI, normal neurologic examination, and negative head CT can be safely discharged 3.
Home observation with frequent waking or pupil checks is NOT supported by evidence and is not recommended 3.
Mandatory Discharge Instructions
Patients must return immediately for 3:
- Repeated vomiting
- Worsening headache
- Memory problems or confusion
- Focal neurologic deficits
- Abnormal behavior
- Increased sleepiness or loss of consciousness
- Seizures
Post-Concussive Syndrome Screening
Screen for persistent symptoms (>3 weeks or sooner if returning to sports) 3:
- Chronic headaches
- Dizziness/balance problems
- Vision problems
- Sensitivity to noise/light
- Depression, anxiety, irritability
- Memory/concentration difficulties
- Sleep disturbances
- Persistent fatigue
Patients with post-concussive symptoms require referral to a TBI specialist and should refrain from strenuous mental or physical activity until symptom-free 3.
Critical Pitfalls to Avoid
- Never allow even brief hypotension in severe TBI—single episodes worsen outcomes 2
- Do not use high-dose glucocorticoids—they increase mortality 2
- Do not routinely use prophylactic antiepileptic drugs—no benefit shown and increased side effects, particularly with phenytoin 2
- Avoid hyperventilation except briefly for impending uncal herniation—maintain PaCO₂ 4.5-5.0 kPa 4
- Do not discharge patients with GCS <15 without imaging regardless of other factors
- Recognize that age >60-65 years significantly increases risk of intracranial injury even with seemingly minor mechanisms 3