Management of Subdural Hematoma

Immediate Assessment and Stabilization

The American College of Cardiology recommends maintaining systolic blood pressure ≥100 mmHg and cerebral perfusion pressure 60-70 mmHg to ensure adequate cerebral perfusion 1, 2
Obtain non-contrast head CT scan to characterize hematoma size, location, mass effect, and midline shift 3
Evaluate specifically for compression of basal cisterns, ventricular effacement, or midline shift >5mm as indicators of increased intracranial pressure 3
Target cerebral perfusion pressure (CPP) 60-70 mmHg if ICP monitoring is established (CPP = MAP - ICP) 3, 1, 2
Hypotension (SBP <90-100 mmHg) is strongly associated with poor outcomes and must be avoided at all costs 2

For patients on vitamin K antagonists (VKA) with INR ≥2.0: administer four-factor prothrombin complex concentrate immediately, followed by intravenous vitamin K to prevent later INR increase 4
For patients on DOACs (dabigatran, apixaban, edoxaban, rivaroxaban): administer specific antidote immediately; if unavailable, use (activated) prothrombin complex concentrate instead 4
For dabigatran specifically, hemodialysis can be considered for drug removal 4
For unfractionated or low-molecular-weight heparin: administer intravenous protamine sulfate 4
For antiplatelet therapy (aspirin, clopidogrel, ticagrelor, prasugrel): do NOT use platelet transfusions, as RCT data suggest worse outcomes in ICH patients receiving antiplatelet therapy who are treated with platelet infusion 4

Immediate surgical evacuation is indicated for subdural hematoma thickness >5mm with midline shift >5mm, development of altered consciousness or new/worsening focal neurological deficits, signs of cerebral herniation or severe intracranial hypertension, or any symptomatic subdural hematoma causing neurological deterioration 3, 1

Close neurological monitoring with serial examinations at least every 4 hours initially is the cornerstone of management 3, 2
Maintain euvolemia to optimize cerebral perfusion 3
Consider repeat imaging at 4-6 weeks to ensure resolution or stability 3
30-40% of subdural hematomas expand in first 12-36 hours, manifesting as neurological deterioration 2

Use mannitol 20% at 250 mOsm dose (0.25 to 2 g/kg body weight as 15-25% solution), infused over 15-20 minutes (or 30-60 minutes per FDA labeling) for threatened intracranial hypertension or signs of brain herniation 5, 1, 2
Maximum effect occurs at 10-15 minutes, lasting 2-4 hours 2
Alternatively, hypertonic saline (3%) can be used 6
Monitor fluid, sodium, and chloride balance with osmotherapy 2
Target serum osmolality 300-310 mOsmol/kg 5

Fronto-parieto-temporo-occipital craniectomy with diameter of at least 12 cm, durotomy, and enlargement duroplasty 5
Removing ischemic brain tissue is not recommended; however, concomitant intracranial bleeding/hematoma can be evacuated 5
ICP monitor placement is recommended 5
Maintain systolic blood pressure >100 mmHg or mean arterial pressure >80 mmHg during all interventions 1

Never allow systolic blood pressure to drop below 90-100 mmHg—this is the most preventable cause of secondary brain injury 2
Do not delay surgery in symptomatic patients with mass effect while awaiting "optimal" timing 1
Do not underestimate small hematomas in anticoagulated elderly patients—they expand rapidly 1
Do not target CPP >70 mmHg routinely—increases complications (respiratory distress syndrome) without neurological benefit 2
Do not use platelet transfusions for antiplatelet-associated ICH—RCT data show worse outcomes 4