Intracranial haemorrhage

• Subarachnoid haemorrhage describes bleeding into the subarachnoid space of the brain, which is located between the arachnoid and pia mater meningeal layers
• SAH can be divided into traumatic or spontaneous

  • Traumatic (tSAH): most common cause of SAH. Usually in setting of a head injury (e.g. fall, assault, road traffic collision)
  • Spontaneous: commonly due to rupture of a cerebral aneurysm (aSAH)
• Multiple blood vessels run along the subarachnoid space, including the circle of willis, which is the main arterial blood supply to the brain. Saccular or berry aneurysms can occur in the circle of willis and this is the main cause of spontaneous subarachnoid haemorrhage
• Risk factors for spontaneous SAH:

  • Hypertension
  • Smoking
  • Family history
  • Over 50 years old
  • Female sex
  • Autosomal dominant polycystic kidney disease - more likely to get berry aneurysms
• Symptoms of SAH:

  • Thunderclap headache
  • Nausea and vomiting
  • Photophobia
  • Seizures
• Clinical findings in SAH:

  • Reduced/loss of consciousness due to raised ICP
  • Neck stiffness
  • Cranial nerve palsy - 3rd nerve palsy
  • Diplopia
• CT head without contrast of SAH will show hyper-attenuation in the subarachnoid space or circle of Willis. The CT is less reliable more than 6 hours after the onset of symptoms.
• A lumbar puncture should be performed if the CT is normal and SAH is suspected. There will be Xanthochromia - a yellow colour to the CSF caused by bilirubin. There will also be raised red and white cell count due to blood leakage into the CSF.
• Once a patient with SAH is stable, a CT angiography is performed to locate the source of the bleeding
• Management of SAH:

  • Calcium channel blocker Nimodipine to present vasospasm that can result in brain ischaemia
  • Surgical intervention - endovascular coiling or neurosurgical clipping
• Subdural haematoma is a collection of blood between the dura mater and arachnoid mater. Can be acute, sub-acute or chronic
• The most common cause of a subdural haematoma is trauma, usually a blow to the temporal side of the head - causes rupture of bridging cranial veins
• Risk factors for subdural haematoma:

  • History of trauma
  • Risk of falls - delirium and dementia
  • Over 65 years old
  • Anticoagulation
  • Alcohol abuse
  • Coagulopathy
• Patients with a subdural haematoma will have a gradual decline vs those with an extradural haematoma
• A subdural haematoma on a CT head will appear as a crescent- shaped collection of blood. Hyperdense blood means an acute bleed, hypodense means a chronic bleed
• Patients with an intracranial bleeds will be managed by:

  • ABCDE approach
  • Correction of coagulation
  • Anticonvulsive mediation
  • Non-surgical management if the bleed is small
  • Surgical management - hemicraniectomy or burr holes
• Extradural haematoma (EDH) is defined as an acute haemorrhage between the dura mater and the inner surface of the skull.
• An extradural haematoma is commonly caused by skull trauma in the temporoparietal region, typically following a fall, assault or sporting injury. An EDH is associated with a skull fracture in 75% of cases.
• The pterion is an anatomical landmark where the parietal, frontal, sphenoid and temporal bones fuse. The pterion is particularly vulnerable to fracture as the bone at this location is relatively thin.
• The middle meningeal artery (MMA) also lies underneath the pterion and therefore fracture at this location can result in rupture of the MMA. As a result, the middle meningeal artery is involved in 75% of extradural haematomas.
• Typical symptoms of EDH include:

  • Headache
  • Nausea and vomiting
  • Confusion
  • Loss of consciousness (typically immediately after a head injury) followed by a period of lucidity
  • Progressively decreasing level of consciousness (typically developing several hours after the initial injury) 
• Typical clinical findings in EDH may include:

  • Tenderness of the skull (in the context of injury)
  • Confusion
  • Reduced Glasgow Coma Score
  • Cranial nerve deficits (e.g. oculomotor nerve palsy causing fixed dilation of the ipsilateral pupil)
  • Motor or sensory deficits of the upper and/or lower limbs (e.g. hemiparesis, paraesthesia)
  • Hyperreflexia and spasticity
  • Upgoing plantar reflex (Babinski’s sign)
  • Cushing’s triad: a physiological response to raised intracranial pressure including bradycardia, hypertension and deep/irregular breathing.
• A CT head is the gold standard investigation in cases of suspected intracranial bleeding. This investigation should be requested urgently if intracranial bleeding is suspected.

  The primary feature on a CT head in the context of EDH is a bi-convex “lemon-shaped” mass (rather than the typical “banana-shape” associated with subdural haemorrhages).
• Patients with an extradural haematoma may receive IV mannitol to reduce intracranial pressure