What is the outcome of a subdural hematoma after craniectomy?

Outcomes of Craniectomy for Subdural Hematoma

Decompressive craniectomy for subdural hematoma may reduce mortality in patients who are deteriorating neurologically or have elevated intracranial pressure refractory to medical management, but its effectiveness in improving functional outcomes remains uncertain.

Mortality Outcomes

• Decompressive craniectomy may be considered as a life-saving measure in patients with subdural hematoma who are deteriorating neurologically, have large hematomas with significant midline shift, or have elevated intracranial pressure (ICP) refractory to medical management 1
• For patients with acute subdural hematoma (ASDH), craniotomy appears to be associated with lower mortality compared to decompressive craniectomy in unmatched cohorts, though this difference disappears in matched populations 2, 3
• In cerebellar hemorrhage with brainstem compression or hydrocephalus, immediate surgical removal is recommended over medical management alone to reduce mortality 1

Functional Outcomes

• The effectiveness of decompressive craniectomy in improving functional outcomes for patients with subdural hematoma remains uncertain 1
• In patients with traumatic acute subdural hematoma, primary decompressive craniectomy may improve favorable outcomes when the initial Glasgow Coma Scale (GCS) score is >4 4
• Functional outcomes after craniotomy versus decompressive craniectomy for ASDH show mixed results across studies, with some suggesting better outcomes with craniotomy 3
• Meta-analyses of surgical interventions for intracerebral hemorrhage provide conflicting results regarding functional outcomes 1

Factors Affecting Outcomes

• Patient characteristics that influence outcomes include:

  • Initial GCS score (worse prognosis with lower scores) 4
  • Age (older patients typically have poorer outcomes) 1
  • Hematoma size and midline shift (larger size and greater shift correlate with worse outcomes) 1
  • Time to surgical intervention (earlier intervention may be beneficial in deteriorating patients) 1

• Surgical considerations that impact outcomes:

  • For supratentorial subdural hematomas >5mm thickness with >5mm midline shift, surgical evacuation is indicated 1
  • The timing of surgery is important, with some evidence suggesting benefit for early intervention (<12 hours) in deteriorating patients 1
  • The choice between craniotomy and decompressive craniectomy should consider the patient's neurological status and ICP 2, 3

Complications and Management

• Common complications after craniectomy for subdural hematoma include:

  • Reaccumulation requiring reoperation 5, 6
  • Wound dehiscence 7
  • Development of hydrocephalus 7
  • Seizures 5
  • Cerebral swelling 6

• Management considerations:

  • Monitoring of ICP and cerebral perfusion pressure is advised following surgery 7
  • Cranioplasty is eventually required to restore skull integrity following decompressive craniectomy 7
  • The timing of cranioplasty must be carefully considered, as early cranioplasty may have a higher complication rate 7

Special Considerations

• For cerebellar hemorrhage, surgical evacuation is strongly recommended for patients who are deteriorating neurologically, have brainstem compression, hydrocephalus, or cerebellar hemorrhage ≥15 mL 1
• In chronic subdural hematoma cases that fail conventional treatments (burr hole or craniotomy with membranectomy), craniectomy may be beneficial for patients with symptomatic reaccumulation or cerebral swelling 6
• The RESCUE-ASDH trial and propensity score-matched studies show similar effectiveness in mortality and functional outcomes between craniotomy and decompressive craniectomy for ASDH 2

Clinical Decision-Making Algorithm

1. Assess patient's neurological status (GCS score) and imaging findings (hematoma size, midline shift)
2. For patients with significant neurological deficit and subdural hematoma >5mm with >5mm midline shift, surgical evacuation is indicated 1
3. For patients who are deteriorating or have elevated ICP refractory to medical management, consider decompressive craniectomy as a life-saving measure 1
4. For cerebellar hemorrhage with brainstem compression or hydrocephalus, proceed with immediate surgical evacuation 1
5. For chronic subdural hematomas that fail conventional treatments, consider craniectomy if there is symptomatic reaccumulation or cerebral swelling 6
6. Following decompressive craniectomy, plan for eventual cranioplasty to restore skull integrity 7