What are the management strategies for high Intracranial Pressure (ICP) in Traumatic Brain Injury (TBI)?

Management of High Intracranial Pressure (ICP) in Traumatic Brain Injury (TBI)

The management of high ICP in TBI requires a stepwise approach, with interventions escalated based on patient response, reserving more aggressive treatments for refractory cases. 1

ICP Monitoring Indications

• ICP monitoring is indicated in severe TBI patients with abnormal CT findings, as more than 50% of these patients will develop intracranial hypertension 1
• ICP monitoring is not routinely recommended when the initial CT scan is normal with no evidence of clinical severity or transcranial Doppler abnormalities 1
• An ICP of 20-40 mmHg is associated with a 3.95 times higher risk of mortality and poor neurological outcome; above 40 mmHg, mortality risk increases 6.9-fold 1

First-Tier Interventions for Elevated ICP

• Head of bed elevation to 20-30° to assist venous drainage and minimize edema formation 1
• Sedation and analgesia following protocols similar to non-brain injured patients, with modifications for ICP control 1
• Maintain adequate cerebral perfusion pressure (CPP) ≥ 60 mmHg when ICP monitoring is available 1
• Osmotherapy with mannitol or hypertonic saline for cerebral edema reduction 2, 3
• Controlled ventilation to maintain PaCO2 between 35-40 mmHg during routine management 1
• CSF drainage via external ventricular drain if available 3

Second-Tier Interventions for Refractory ICP

• Temporary hyperventilation (PaCO2 30-35 mmHg) for acute ICP crises or signs of herniation 1
• Higher-dose osmotherapy with close monitoring of serum osmolarity and electrolytes 3
• Neuromuscular blockade to eliminate posturing or ventilator dyssynchrony that may increase ICP 3, 4

Third-Tier Interventions for Persistent Elevation

• Barbiturate coma for refractory intracranial hypertension, though associated with significant hemodynamic effects requiring careful monitoring 2
• Decompressive craniectomy may reduce mortality (26.9% vs 48.9% in medical management) but potentially at the expense of increased severe disability 1
• The RESCUE-ICP study showed decompressive craniectomy reduced mortality compared to barbiturate coma but did not improve favorable outcomes at 6 months 1

Critical Parameters to Maintain

• Oxygenation: Maintain PaO2 between 60-100 mmHg 1
• Ventilation: Maintain PaCO2 between 35-40 mmHg (except during temporary hyperventilation for herniation) 1
• Coagulation: Maintain platelet count >50,000/mm³ for life-threatening hemorrhage and higher for neurosurgical interventions 1
• Hemostasis: Keep PT/aPTT <1.5 times normal control during interventions 1

Special Considerations

• In cases of cerebral herniation, osmotherapy and/or temporary hypocapnia are recommended while awaiting definitive management 1
• Point-of-care coagulation tests (TEG, ROTEM) should be utilized when available to guide coagulation management 1
• For patients requiring both neurosurgical intervention and treatment for life-threatening hemorrhage elsewhere, protocols for simultaneous multisystem surgery should be established 1
• Recent data suggests ICP monitoring is associated with decreased inpatient mortality (35.1% vs 42.4%) despite longer hospital stays and higher costs 5

Pitfalls to Avoid

• Daily interruption of sedation may be harmful in TBI patients with signs of high ICP 1
• Avoid hypotension, as decreased cerebral perfusion pressure below 60 mmHg can worsen brain edema and secondary injury 1
• Corticosteroids have not shown benefit in TBI and are not recommended for ICP control 1
• Bifrontal craniectomy was associated with worse outcomes in the DECRA study and should be used cautiously 1
• Avoid hypo-osmolar fluids that may worsen cerebral edema 1