What are the tiered approaches for managing traumatic brain injury?

Tiered Approaches for Managing Traumatic Brain Injury

The management of traumatic brain injury (TBI) follows a tiered approach with controlled normothermia (36.0-37.5°C) included in Tier 1 and Tier 2, and therapeutic hypothermia (≤36.0°C) considered in Tier 3 when other measures fail to control intracranial pressure. 1

Initial Assessment and Transfer

• Severe TBI patients should be managed by a pre-hospital medicalized team and transferred as soon as possible to a specialized center with neurosurgical facilities 1, 2
• Systolic blood pressure should be maintained >110 mmHg prior to measuring cerebral perfusion pressure to prevent secondary brain injury 1
• Brain and cervical CT scan should be performed without delay in severe TBI patients to diagnose primary brain lesions and guide neurosurgical procedures 1, 2

Tiered Management Protocol

Tier Zero (Not ICP Dependent)

• Treat core temperature >38.0°C 1
• Provide sedation, endotracheal intubation, and mechanical ventilation 1
• Maintain CPP >60 mmHg 1
• Maintain SpO₂ >94% and hemoglobin >7g/dL 1
• Consider EEG monitoring and seizure prophylaxis, avoid hyponatremia 1

Tier 1 Interventions

• Implement controlled normothermia (target core temperature 36.0-37.5°C) 1
• Titrate sedation and analgesia to control ICP 1
• Maintain CPP 60-70 mmHg 1
• Target PaCO₂ 35-38 mmHg (4.7-5.1 kPa) 1
• Consider osmotherapy (mannitol) and external ventricular drainage 1

Tier 2 Interventions

• Continue controlled normothermia (target core temperature 36.0-37.5°C) 1
• Individualize CPP goals 1
• Target PaCO₂ 32-35 mmHg (4.3-4.7 kPa) 1
• Consider external ventricular drainage to treat persisting intracranial hypertension despite sedation and correction of secondary brain insults 1

Tier 3 Interventions

• Consider therapeutic hypothermia (target core temperature ≤36.0°C) when Tier 1 and 2 treatments have failed to control ICP 1
• If hypothermia is considered, target temperature should be managed as close to normothermia as possible 1
• Consider decompressive craniectomy to control refractory intracranial pressure after multidisciplinary discussion 1

Neurosurgical Interventions

• Neurosurgical indications in the early phase of severe TBI include 1:
  • Removal of symptomatic extradural hematoma regardless of location
  • Removal of significant acute subdural hematoma (thickness >5 mm with midline shift >5 mm)
  • Drainage of acute hydrocephalus
  • Closure of open displaced skull fracture
  • Management of closed displaced skull fracture with brain compression

Pharmacological Management

Mannitol for ICP Management

• Indicated for reduction of intracranial pressure and brain mass 3
• Adult dosage: 0.25 to 2 g/kg body weight as a 15% to 25% solution administered over 30-60 minutes 3
• Pediatric dosage: 1 to 2 g/kg body weight or 30 to 60 g/m² body surface area over 30-60 minutes 3
• Monitor for renal complications, fluid and electrolyte imbalances, and CNS toxicity 3
• Avoid concomitant administration of nephrotoxic drugs or other diuretics 3

Ventilation Strategies

• Airway control is a priority, and pre-hospital tracheal intubation decreases mortality in trauma patients 1
• End-tidal CO₂ monitoring is critical to check correct tracheal tube placement and maintain PaCO₂ within range 1
• Avoid hyperventilation as it can cause cerebral vasoconstriction and worsen secondary brain injury 4
• For patients with severe TBI who develop ARDS, a protective ventilation strategy is recommended with tidal volumes of 6-8 ml/kg PBW for moderate respiratory failure and 4-6 ml/kg PBW for severe respiratory failure 5

Common Pitfalls to Avoid

• Hypotension (systolic BP <110 mmHg) significantly worsens outcomes in TBI patients and should be prevented 1, 2
• Hyperventilation therapy should not be used prophylactically as it can exacerbate secondary brain injury by decreasing cerebral blood flow 4
• Biomarkers should not be used in clinical routine for initial TBI severity assessment as their utility remains uncertain 1, 2
• Avoid hyperoxia after stabilization as it may worsen outcomes 6, 2

Special Considerations

• For multiple trauma with TBI, management of life-threatening injuries should be prioritized while avoiding secondary brain injury 2
• Arterial hypotension is a major risk factor for secondary brain injury, but hypertension with loss of autoregulation response can also result in poor outcomes 7
• Systemic inflammatory response syndrome after TBI reflects the extent of tissue damage and predicts further tissue disruption 7