How should I manage a patient with a known subdural hematoma who fell and may have sustained another head injury?

Management of Known Subdural Hematoma with Fall and Possible Re-injury

Obtain an urgent non-contrast head CT immediately to assess for hematoma expansion, new bleeding, or increased mass effect, followed by neurological examination including Glasgow Coma Scale and pupillary assessment to determine if emergency neurosurgical intervention is required. 1, 2

Immediate Assessment Protocol

Neurological Evaluation

• Assess Glasgow Coma Scale motor score and perform pupillary examination immediately – abnormal pupils (anisocoria or bilateral mydriasis) indicate herniation risk and constitute an absolute indication for emergency surgical evacuation 1, 2
• Document any focal neurological deficits including motor weakness, sensory changes, or speech disturbances that may indicate hematoma expansion 1
• A decline in GCS score of 2 points or more from baseline warrants emergency surgery 1

Imaging Strategy

• Non-contrast head CT is mandatory and must be obtained within 3 hours – this is the gold standard for detecting acute intracranial hemorrhage and assessing for expansion of the known subdural hematoma 1
• Approximately 28-38% of patients demonstrate hematoma expansion on subsequent imaging after initial injury 1
• Measure maximal hematoma thickness and degree of midline shift – immediate surgical evacuation is indicated if thickness >10 mm or midline shift >5 mm with neurological symptoms 1, 2
• CT angiography should be obtained if there is concern for active bleeding, as contrast extravasation identifies patients at high risk for further expansion 1

Decision Algorithm for Surgical vs. Conservative Management

Immediate Surgical Indications (Proceed to Emergency Craniotomy)

• Rapidly deteriorating neurological examination 2
• Unilaterally or bilaterally dilated nonreactive pupils 2
• Extensor posturing 2
• Hematoma thickness >10 mm 2
• Midline shift >5 mm with symptoms 1, 2
• Signs of impending herniation (compressed basal cisterns, ventricular effacement) 1

Conservative Management with Close Monitoring

• Small or stable hematomas without significant neurological deficits should be managed conservatively with serial neurological assessments and repeat imaging 1, 2, 3
• Maintain systolic blood pressure >100 mmHg or mean arterial pressure >80 mmHg 4, 1
• Maintain euvolemia – avoid both hypovolemia and hypervolemia as hypervolemia does not improve outcomes and may cause complications 1, 2
• Serial CT imaging is necessary to monitor for delayed progression 2, 3

Critical Management Considerations

Anticoagulation Status

• If the patient is on anticoagulation, rapidly reverse with prothrombin complex concentrate plus vitamin K before any surgical intervention 1, 2
• Target prothrombin time/activated partial thromboplastin time <1.5 times normal control before neurosurgical procedures 1
• Platelet count should be >50,000/mm³ minimum for hemorrhage control 1

Hemodynamic Targets During Intervention

• Maintain systolic blood pressure >100 mmHg or mean arterial pressure >80 mmHg during emergency interventions 4, 1
• If ICP monitoring is placed, maintain cerebral perfusion pressure ≥60 mmHg 1
• Target PaO₂ between 60-100 mmHg and PaCO₂ between 35-40 mmHg 1

ICP Monitoring Indications

• ICP monitoring is indicated if any of the following are present: pre-operative motor GCS ≤5, pre-operative anisocoria or bilateral mydriasis, hemodynamic instability, compressed basal cisterns, midline shift >5 mm, or intra-operative cerebral edema 1
• ICP monitoring is NOT required if initial CT is normal with no clinical severity indicators 1
• Intraparenchymal probes are preferred over intraventricular drains (lower infection rate: 2.5% vs 10%; lower hemorrhage risk: 0-1% vs 2-4%) 1

Common Pitfalls to Avoid

Do Not Delay Surgery for "Medical Optimization"

• Never delay surgical evacuation beyond basic resuscitation when clear surgical indications exist – delaying surgery for medical optimization worsens prognosis in patients with neurological deterioration 1, 2
• Mannitol and hyperventilation serve only as temporary bridges to definitive surgery in impending herniation, not as standalone treatments 1

Recognize Delayed Presentation Risk

• Even with negative initial imaging, delayed subdural hematoma can develop weeks to months after mild head injury 5, 6
• Unsteady gait and ataxia are uncommon in postconcussion syndrome and should prompt repeat CT imaging 6
• For patients on anticoagulation with negative initial CT, delayed intracranial hemorrhage is rare (0.6% for warfarin patients), but 24-hour observation with repeat CT at 20-24 hours is recommended 1

Post-Intervention Management

• Do NOT use antiepileptic drugs for primary prevention of post-traumatic seizures – they show no benefit and may worsen neurological outcomes 1, 2
• Consider antiepileptic drugs only if specific risk factors are present (chronic subdural hematoma with prior epilepsy) 2
• Maintain cerebral perfusion pressure between 60-70 mmHg in adults without multimodal neuromonitoring 1

Follow-up for Conservative Management

• Close outpatient follow-up is essential for patients discharged with conservative management 3
• Patient education regarding warning signs (worsening headache, altered consciousness, new focal deficits, vomiting) requiring immediate return 3
• Consider repeat imaging at 4-6 weeks to ensure resolution or stability 3