Treatment of Subdural Hematoma
Immediate surgical evacuation is indicated for symptomatic subdural hematoma with significant mass effect, neurological deterioration, or decreased level of consciousness, while stable patients with small or asymptomatic hematomas can be managed conservatively with close monitoring. 1
Initial Assessment and Surgical Triage
The decision between surgical and conservative management hinges on three key factors 1:
- Neurological status: Assess Glasgow Coma Scale (GCS), pupillary examination, and focal neurological deficits 1
- Hematoma characteristics: Measure maximal thickness and degree of midline shift on CT imaging 1
- Clinical symptoms: Evaluate for headache, altered consciousness, vomiting, and progressive symptoms 1
Surgical Indications and Approach
Acute Subdural Hematoma
Immediate surgical evacuation is required for 1:
- Symptomatic hematoma with significant mass effect
- Neurological deterioration
- Decreased level of consciousness
The underlying brain injury severity is more critical to outcome than the absolute timing of surgery, though earlier intervention shows favorable trends 2. However, do not delay surgical intervention when neurological deterioration occurs, as this leads to poorer outcomes 1.
Chronic Subdural Hematoma
Burr hole drainage is the preferred first-line surgical approach 1:
- Place subdural drain postoperatively to reduce recurrence rates (which range from 2-37%) 1, 3
- Most recurrent hematomas are successfully managed with repeat burr hole craniostomies with closed-system drainage 3
Emerging Minimally Invasive Option
For acute subdural hematoma in patients with GCS ≥13, hematoma thickness ≥7 mm, and no need for immediate evacuation, twist-drill craniostomy with pressure-controlled fibrinolytic irrigation (TDC-FIT) achieved 90% independence at 3 months compared to 56.7% with open craniotomy 4.
Conservative Management Strategy
Conservative management with close monitoring is appropriate for stable patients without significant neurological deficits, particularly for small or asymptomatic hematomas 1:
- Perform regular neurological assessments 1
- Maintain euvolemia (avoiding hypervolemia, which does not improve outcomes and may cause complications) 1
- Obtain serial imaging to monitor for progression 1
- Spontaneous resolution can occur in rare cases, particularly with smaller hematomas 5
Anticoagulation Management
Rapidly reverse anticoagulation using prothrombin complex concentrate plus vitamin K for patients on anticoagulation who develop subdural hematoma 1:
- Interrupt anticoagulation for typically 7-15 days 1
- The risk of ischemic events during this period is low 1
Adjunctive Medical Therapy
Mannitol may be used for reduction of intracranial pressure and brain mass 6:
- Exerts osmotic diuretic effect by inducing movement of intracellular water to extracellular and vascular spaces 6
- Elimination half-life is 0.5 to 2.5 hours in normal renal function 6
Nonsurgical alternatives (dexamethasone, tranexamic acid, middle meningeal artery embolization) remain investigational and should be considered only as adjunct therapy, particularly for recurrent hematoma 7.
Special Consideration: Subdural Hematoma with Spontaneous Intracranial Hypotension
When subdural hematoma occurs in the context of spontaneous intracranial hypotension, perform MRI of brain with contrast and whole spine to investigate for spinal CSF leak 1.
Critical Pitfalls to Avoid
- Never delay surgical intervention when neurological deterioration occurs 1
- Avoid hypervolemia, as it does not improve outcomes and may cause complications 1
- The extent of primary underlying brain injury is more important than the subdural clot itself in dictating outcome; therefore, aggressive postoperative control of intracranial pressure (particularly keeping ICP <45 mmHg) is critical 2