Subdural Haemorrhage

Question 1

Define Subdural Haemorrhage

Answer 1

Collection between the dura mater and the surface (arachnoid covering) of the brain

Question 2

Aetiology of Subdural Haemorrhage

Answer 2

Trauma to the head
Cerebral aneurysm rupture
Vascular malformation: arteriovenous malformation or dural fistula
Rare: cerebral hypotension and malignancy

Torsional or shear force causes disruption of the bridging cortical veins emptying the dural venous sinuses

Question 3

Risk factors for Subdural Haemorrhage

Answer 3

Recent trauma (more likely falls and assault than motor vehicle)
Elderly 
Alcoholics
Coagulopathy and anticoagulant use
Advanced age >65

Question 4

Symptoms of Subdural Haemorrhage

Answer 4

Headache (gradual onset, continuous/constant, subacute -> worsening 7-14 days after injury)
Raised ICP: early morning headache, nausea and vomiting
Drowsiness
Personality change
Loss of bowel and bladder continence
Basilar skull fracture: otorrhoea, rhinorrhoea

Question 5

Signs of Subdural Haemorrhage of examination

Answer 5

Acute:
Reduced GCS
Ipsilateral fixed dilated pupil (midline shift - compresses CNIII parasympathetic fibres)
Brainstem pressure - very reduced GCS, bradycardia

Subacute:
Altered mental status

Chronic:
Cognitive impairment
Gait deterioration
Focal weakness
Seizures
Focal neurological signs (CN III or VI dysfunction, papilloedema, hemiparesis)

Question 6

Investigations for Subdural Haemorrhage

Answer 6

Urgent CT head (non-contrast): Crescent shape that is hyperdense (acute) or hypodense/like CSF (chronic)
Non-contrast to prevent leakage into the brain tissue

MRI brain
Plain skull X-ray: possible skull fracture or presence of intracranial shrapnel

Question 7

Management for Acute Subdural Haemorrhage

Answer 7

1. Observe, monitor
2. Prophylactic antiepileptics e.g. phenytoin
3. Correct coagulopathies
4. ICP lowering regimen
   - Raised head of bed to 30
   - Reverse Trendelenberg position
   - Consider osmotic diuresis with mannitol

If ≥10 mm size or midline shift >5 mm or expansile or significant neurological dysfunction => Burr hole or craniotomy initially

Question 8

Management for chronic Subdural Haemorrhage

Answer 8

1. Antiepileptics e.g. phenytoin IV
2. Elective surgery (twist-drill craniotomy + catheter drainage OR Burr hole)
3. Correct coagulopathy
4. ICP lowering regimen
   - Raised head of bed to 30
   - Reverse Trendelenberg position
   - Consider osmotic diuresis with mannitol

Question 9

Complications of Subdural Haemorrhage

Answer 9

Neurological deficits e.g. raised ICP, cerebral oedema
Coma
Stroke
Surgical-site infection
Epilepsy
Recurrence of subdural haematoma post-op (33%)