What are the guidelines for managing traumatic brain injury in the Intensive Care Unit (ICU)?

Guidelines for Managing Traumatic Brain Injury in the ICU

The management of traumatic brain injury (TBI) in the ICU requires a stepwise approach with interventions escalated based on patient response, with ICP monitoring strongly indicated in severe TBI patients with abnormal CT findings as more than 50% will develop intracranial hypertension. 1

Initial Assessment and Monitoring

• Severe TBI is defined as Glasgow Coma Scale (GCS) ≤8, moderate TBI as GCS 9-13, and mild TBI as GCS 14-15 1
• ICP monitoring is strongly indicated in severe TBI patients with abnormal CT findings, as the incidence of high ICP varies between 17-88% in these patients 2, 1
• ICP monitoring should not be performed if the initial CT scan is normal with no evidence of clinical severity or transcranial Doppler abnormalities 2
• Consider ICP monitoring after evacuation of post-traumatic intracranial hematoma if any of these criteria are present: preoperative GCS motor response ≤5, preoperative anisocoria/mydriasis, hemodynamic instability, severity signs on imaging, intraoperative cerebral edema, or postoperative new lesions 2

First-Tier Interventions

• Maintain cerebral perfusion pressure (CPP) between 60-70 mmHg in adults without multi-modal monitoring 2, 1
• Position the head of bed at 20-30° to assist venous drainage and minimize edema 3
• Provide sedation and analgesia following protocols similar to non-brain injured patients, with modifications for ICP control 3
• Maintain PaCO₂ between 35-40 mmHg during routine management 1, 3
• Avoid hypotension as decreased CPP below 60 mmHg can worsen brain edema and secondary injury 1, 3

Second-Tier Interventions for Refractory Intracranial Hypertension

• Use osmotherapy with hypertonic saline or mannitol for refractory intracranial hypertension 1
• Consider temporary hyperventilation (PaCO₂ 30-35 mmHg) for acute ICP crises or signs of herniation 3
• Avoid hypo-osmolar fluids that may worsen cerebral edema 1, 3

Third-Tier Interventions

• Consider decompressive craniectomy to control intracranial pressure in the early phase of TBI with refractory intracranial hypertension after multidisciplinary discussion 2
• Be aware that decompressive craniectomy may reduce mortality (26.9% vs 48.9% in medical management) but potentially at the expense of increased severe disability 2, 3
• The RESCUE-ICP study showed that while mortality was reduced with decompressive craniectomy compared to barbiturate coma (26.9% vs 48.9%), favorable outcome at 6 months was not significantly different (27.4% vs 26.6%) 2
• Bifrontal craniectomy was associated with worse outcomes in the DECRA study and should be used cautiously 3

Critical Parameters to Maintain

• Oxygenation: Maintain PaO₂ between 60-100 mmHg 1, 3
• Ventilation: Maintain PaCO₂ between 35-40 mmHg (except during temporary hyperventilation for herniation) 1, 3
• Coagulation: Maintain platelet count >50,000/mm³ for life-threatening hemorrhage and higher for neurosurgical interventions 3
• Hemostasis: Keep PT/aPTT <1.5 times normal control during interventions 3

Management of TBI with Polytrauma

• For patients with both TBI and extracranial injuries causing bleeding, there is a challenging balance between addressing life-threatening hemorrhage and preventing secondary brain injury 1
• Avoid "permissive hypotension" strategies in TBI patients as arterial hypotension exacerbates cerebral secondary damage 1
• For patients requiring both neurosurgical intervention and treatment for life-threatening hemorrhage elsewhere, establish protocols for simultaneous multisystem surgery 3

Pitfalls to Avoid

• Daily interruption of sedation may be harmful in TBI patients with signs of high ICP 3
• Avoid hypotension, as decreased cerebral perfusion pressure below 60 mmHg can worsen brain edema and secondary injury 1, 3
• Corticosteroids have not shown benefit in TBI and are not recommended for ICP control 3
• Avoid hypo-osmolar fluids that may worsen cerebral edema 1, 3
• 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 2, 1