Management of Subdural Hematoma
Immediate Surgical Indications
Immediate surgical evacuation is required for symptomatic subdural hematomas with significant mass effect, neurological deterioration, or decreased level of consciousness. 1
Specific criteria requiring urgent surgery include:
- SDH thickness >10 mm or midline shift >5 mm 2
- Rapidly deteriorating neurological exam 2
- Unilaterally or bilaterally dilated nonreactive pupils 2
- Extensor posturing 2
- Clinical evidence of intracranial hypertension or significant neurologic dysfunction 3
Conservative Management Criteria
Small or asymptomatic subdural hematomas can be managed conservatively with close monitoring. 4, 1
Patients appropriate for non-operative management:
- Glasgow Coma Scale (GCS) scores 11-15 with minimal symptoms 3, 5
- SDH ≤3 mm thickness (no patient in this category required surgery) 6
- Absence of focal neurological deficits 3
- Open cisterns on imaging 3
- Minimal mass effect on CT 5
Conservative management requires:
- Regular neurological assessments with serial imaging to monitor for progression 1
- Maintaining euvolemia (avoiding hypervolemia which does not improve outcomes) 1, 7
- Head elevated positioning as comfortable 4
Medical Management Parameters
Cerebral perfusion pressure should be maintained between 60-70 mmHg in the absence of multi-modal monitoring. 4
Additional targets include:
For intracranial hypertension:
- Administer mannitol 20% or hypertonic saline solution at 250 mOsm over 15-20 minutes 4
Anticoagulation Reversal
Rapidly reverse anticoagulation using prothrombin complex concentrate plus vitamin K for patients on anticoagulation who develop subdural hematoma. 1
- Duration of anticoagulation interruption is typically 7-15 days 1
- Low risk of ischemic events during this period 1
Surgical Technique Selection
Burr hole drainage is the preferred first-line surgical approach for chronic subdural hematomas, with subdural drain placement to reduce recurrence rates. 1
Surgical approach based on SDH characteristics:
- Chronic SDH without septations: Burr hole drainage or twist drill craniostomy 2
- Chronic SDH with septations: Craniotomy with or without membranectomy 2
- Acute SDH with significant mass effect and cerebral edema: Craniotomy with clot evacuation, frequently requiring craniectomy 2
Risk Factors for Hematoma Expansion
Larger initial SDH size, concurrent subarachnoid hemorrhage, hypertension, convexity location, and midline shift are significantly associated with hematoma expansion. 6
- An 8.5-mm initial SDH size threshold best predicts the need for surgical intervention 6
- SDH enlargement occurs in approximately 25% of patients with follow-up imaging 6
- Patients with large aSDHs trend toward higher progression (36% vs 16%) and higher rates of chronic SDH surgery (25% vs 7%) 5
Post-operative Care
Patients should be positioned with head elevated as comfortable. 4
Additional post-operative measures:
- Thromboprophylaxis should be considered during immobilization following procedures 4
- ICU level care co-managed by neurointensivists 7
- Early initiation of enteral feeding, mobilization, and physical therapy 7
- Maintenance of normothermia, eucarbia, euglycemia, and euvolemia 7
Follow-up Monitoring
Patients should be advised to seek urgent medical attention for new-onset severe headache, neurological deficits, or altered mental status. 4
- Approximately 6% of patients managed nonsurgically develop chronic SDH requiring craniotomy 3
- Serial imaging is essential to monitor for progression in conservatively managed patients 1
Critical Pitfalls to Avoid
Do not delay surgical intervention when neurological deterioration occurs, as this leads to poorer outcomes. 1