Treatment of Subdural Hematoma (SDH)
The treatment of subdural hematoma depends critically on whether it is acute or chronic, the patient's neurological status, and specific imaging characteristics—with surgical evacuation being the primary treatment for symptomatic cases, while selected minimally symptomatic patients can be managed conservatively with close monitoring.
Acute Subdural Hematoma (ASDH)
Immediate Assessment and Stabilization
Rapidly reverse any coagulopathy immediately upon diagnosis, as elevated INR is associated with larger hematoma volumes and worse outcomes 1:
- For warfarin: Administer prothrombin complex concentrate or fresh frozen plasma plus vitamin K to normalize INR within 15 minutes 1
- For heparin: Give protamine sulfate, with dosing based on time since last heparin dose 1
- Discontinue all anticoagulants and antiplatelet agents for at least 1-2 weeks during the acute period 1
Maintain critical physiological parameters 2:
- Intracranial pressure (ICP) < 22 mmHg 2
- Cerebral perfusion pressure (CPP) 60-70 mmHg 1, 2
- Mean arterial pressure (MAP) 80-110 mmHg 2
- PaO2 > 60 mmHg 2
Administer mannitol 20% or hypertonic saline for intracranial hypertension 1
Surgical Decision-Making
Urgent surgical evacuation via craniotomy or craniectomy is indicated when 3:
- Clot thickness exceeds 10 mm, regardless of neurological condition 3
- Midline shift is greater than 5 mm, regardless of neurological condition 3
- Clinical evidence of intracranial hypertension or significant neurologic dysfunction is present 4
Conservative management is appropriate for selected patients with 4:
- Glasgow Coma Scale (GCS) scores of 11-15 4
- Clot thickness ≤ 1 cm 4
- No focal neurological deficits 4
- Open cisterns on imaging 4
- No signs of intracranial hypertension 4
In the study of minimally symptomatic ASDH patients, 93% of those managed nonsurgically achieved functional recovery, with only 6% developing chronic SDH requiring delayed craniotomy 4. There appears to be no advantage in evacuating the clot unless it is causing clinical evidence of intracranial hypertension or significant neurologic dysfunction 4.
Surgical Technique
Craniotomy or craniectomy is preferred over burr holes for acute SDH evacuation based on available data 3. The timing of surgery has not been associated with outcome differences in minimally symptomatic patients 4.
Post-Operative Management
Position the patient with head elevated as comfortable 1
Implement seizure prophylaxis with anti-seizure medications 2, 3
Monitor for 3:
- Resolution of pneumocephalus 3
- Signs of SDH reaccumulation 3
- Complications including subdural hematomas (11% incidence in some series) 5
Thromboprophylaxis timing must balance thrombotic versus hemorrhagic risk 1:
- For very high thromboembolism risk: Consider restarting warfarin at 7-10 days post-hemorrhage 1
- For lower thromboembolism risk: Consider antiplatelet agents instead of full anticoagulation 1
Chronic Subdural Hematoma (CSDH)
First-Line Treatment
Surgical evacuation remains the first-line treatment for CSDH 6. However, the elderly are especially prone to poor surgical outcomes, and many are on anticoagulants/antiplatelet agents, increasing rebleeding risk 6.
Nonsurgical Alternatives
Dexamethasone should be used with caution for selected patients given its side effects 6
Tranexamic acid may be utilized as adjunct therapy to surgery, though more randomized clinical trials are needed to evaluate its definitive efficacy 6
Middle meningeal artery embolization (MMAE) has shown interesting results in case studies, but risks including intracerebral hemorrhage, stroke, and vasospasm have not been properly studied 6
Atorvastatin and ACE inhibitors have uncertain clinical benefits for CSDH 6
Pediatric Considerations (Children < 2 Years)
For traumatic SDH in children younger than 2 years, subdural-peritoneal shunt placement is the most commonly required definitive treatment (48% of surgical cases), though it carries a 26% complication rate 7:
- Transcutaneous subdural puncture requires further intervention in 82% of cases 7
- External subdural drainage requires further intervention in 50% of cases 7
- Bilateral drainage is only required in 9.4% despite 52% having bilateral SDH 7
Critical Monitoring
Close neurological monitoring is essential to detect early signs of altered CSF dynamics and complications 5
Advise patients to seek urgent care for 1:
Common pitfall: Paradoxical herniation can develop post-operatively and requires immediate Trendelenburg positioning and potentially intravenous fluid administration 5.