What is the proper assessment and management of a head injury?

Assessment of Head Injury

All head-injured patients require immediate clinical evaluation using the Glasgow Coma Scale (GCS) combined with urgent CT imaging for moderate-to-severe injuries, while simultaneously preventing secondary brain insults—particularly hypotension and hypoxia—which are the most modifiable determinants of mortality and neurological outcome. 1, 2

Initial Clinical Assessment

Severity Classification by GCS

• Severe TBI: GCS ≤ 8 - requires immediate intubation, CT scan, and ICU admission 1, 2
• Moderate TBI: GCS 9-13 - mandates CT scan and frequent neurological monitoring (every 30-60 minutes initially) 1
• Mild TBI: GCS 14-15 - requires selective CT imaging based on specific risk factors 1

Critical Components to Assess

• Motor score is the most robust GCS component, especially in sedated patients 2
• Pupil size and reactivity must be documented repeatedly as key prognostic indicators 2
• Vital signs with particular attention to blood pressure and oxygen saturation 1

Immediate Priorities: Prevent Secondary Brain Injury

Blood Pressure Management

Maintain systolic blood pressure >110 mmHg in adults aged 15-49 years and >70 years; maintain >100 mmHg for ages 50-69 years. 1 Even a single episode of hypotension (SBP <90 mmHg) for ≥5 minutes increases mortality significantly. 1 The combination of hypotension and hypoxia carries a devastating 75% mortality rate. 1

• Target mean arterial pressure ≥80 mmHg in severe TBI 1
• Use vasopressors (phenylephrine, norepinephrine) immediately via peripheral IV if needed 1
• Avoid hypotensive sedatives during intubation 1

Oxygenation and Ventilation

Control airway immediately in severe TBI through endotracheal intubation with continuous end-tidal CO₂ monitoring, even in the prehospital setting. 1

• Maintain SaO₂ >90% at all times; duration of hypoxemic episodes predicts mortality 1
• Target PaCO₂ 35-40 mmHg; avoid hypocapnia which causes cerebral vasoconstriction and ischemia 1
• Monitor end-tidal CO₂ continuously to verify tube placement and maintain appropriate ventilation 1

CT Imaging Protocol

Mandatory CT Indications

Perform brain and cervical spine CT immediately without delay in: 1

• All severe TBI (GCS ≤8)
• All moderate TBI (GCS 9-13)
• Mild TBI (GCS 14-15) with ANY of the following:
  • Basal skull fracture signs (rhinorrhea, otorrhea, hemotympanum, Battle's sign, raccoon eyes)
  • Displaced skull fracture
  • Post-traumatic seizure
  • Focal neurological deficit
  • Coagulopathy or anticoagulant therapy 1

CT-Angiography Indications

Add CT-angiography of supra-aortic and intracranial vessels if: 1

• Cervical spine fracture present
• Focal deficit unexplained by brain CT
• Horner syndrome
• LeFort II/III facial fractures
• Basal skull fractures
• Soft tissue neck injury 1

Structured Neurological Monitoring

Frequency of Reassessment

For moderate TBI (GCS 9-13), repeat neurological examination: 1

• Every 15 minutes for first 2 hours
• Then hourly for next 12 hours
• Repeat CT immediately if GCS drops ≥2 points or new neurological deficit appears 1

For severe TBI, continuous monitoring with: 1

• Hourly GCS and pupil checks minimum
• Consider ICP monitoring (see below)

Advanced Monitoring Adjuncts

Transcranial Doppler (TCD)

Consider TCD on emergency department arrival to assess cerebral perfusion. 1 Poor prognostic indicators include:

• Diastolic velocity <20-25 cm/s
• Pulsatility index >1.25-1.4
• Mean velocity <28 cm/s 1

These values predict secondary neurological deterioration and should trigger aggressive intervention. 1

Intracranial Pressure Monitoring

Insert ICP monitor in severe TBI when: 1

• GCS ≤8 with abnormal CT (hematomas, contusions, edema, compressed cisterns)
• GCS ≤8 with normal CT but ≥2 of: age >40, motor posturing, SBP <90 mmHg 1

Target cerebral perfusion pressure (CPP) ≥60 mmHg once ICP monitoring available, adjusting based on autoregulation status. 1

Management of Intracranial Hypertension

Stepwise Approach for Elevated ICP

1. First-line: Adequate sedation, head elevation 30°, maintain normocapnia 1
2. Second-line: External ventricular drainage if ventricles accessible 1
3. Osmotic therapy: Mannitol 0.25-2 g/kg IV over 30-60 minutes 3 or hypertonic saline for clinical herniation 2
4. Last resort: Decompressive craniectomy for refractory ICP after multidisciplinary discussion 1

Critical Pitfalls to Avoid

• Never delay CT for "stabilization" in moderate-severe TBI—imaging guides all subsequent decisions 1
• Never use corticosteroids—they provide no benefit and may increase mortality 2
• Never tolerate hypotension even briefly; this is the single most preventable cause of poor outcome 1
• Avoid aggressive hyperventilation (PaCO₂ <35 mmHg) except for acute herniation—it worsens ischemia 1
• Do not use biomarkers (S100b, etc.) for routine clinical decision-making—insufficient evidence 1

Polytrauma Considerations

In patients with both TBI and life-threatening hemorrhage, implement simultaneous multisystem surgery protocols involving neurosurgery and trauma surgery teams operating concurrently to minimize time to hemorrhage control while preventing secondary brain injury. 1 This approach requires pre-established institutional protocols but significantly improves outcomes. 1

Maintain 1:1:1 ratio of RBCs:plasma:platelets during massive transfusion, then adjust based on laboratory values and viscoelastic testing (TEG/ROTEM). 1