Condition-Subarachnoid Haemorrhage

Question 1

Describe the layers of meninges and what a subarachnoid haemorrhage is…

Answer 1

Meninges:

1. Skulls cap
2. Epidural Space
3. Dura Mater
4. Subdural Space
5. Arachnoid mater
6. Subarachnoid space
7. Pia Mater

SAH: Arterial Haemorrhage into subarachnoid space

Question 2

What is the most common cause of a SAH?

Answer 2

Berry Aneurysms- a rupture of a saccular aneurysm at the base of the brain (85%)

Other causes: arteriovenous malformations, vertebral artery dissection

Question 3

List some risk factors that predispose people to SAH…

Answer 3

• Hypertension
• Smoking
• Alcohol
• Bleeding disorder
• Increased risk berry aneurysms

Question 4

List some risk factors for developing Berry Aneurysms…

Answer 4

• Polycystic kidney disease
• Coarction of the aorta
• Marfan’s syndrome
• Ehlers-Danlos syndrome
• SLE

Question 5

Where is the most likely place for Berry Anerysms to occur?

Answer 5

Between the junctions of vessels in the circle of Willis. Most common is the anterior cerebral/ anterior communicating junction

Question 6

Descibe the presenting symptoms of a patient with SAH…

Answer 6

• Sudden onset worst headache- typically occipital = THUNDER CLAP HEADACHE
• Nausea/ vomitting
• Collapse
• Seizures
• Reduced consciousness
• meningism symptoms:
  
  • Neck stiffess
  • photophobia

Question 7

List some of the signs of SAH on physical examination…

Answer 7

Signs of Meningsmus:

• Kernig’s sign positive
• Neck stiffness
• Pyrexia + photophobia

GCS- deterioration

Signs of rasied ICP- papilloedema, IV or III palsies, Cushing’s sign (HT+Bradycardia)

Question 8

Which investigations could you do to identify SAH?

Answer 8

• Imaging: CT scan
  
  • ​Bedside: BP, HR, GCS
  • Bloods: FBC, U&Es, ESR/CRP, clotting
• Angiography: detect source of bleeding
• Lumbar puncture: If CT-ve

Question 9

What sort of haemorrhage can be seen in this CT? Describe some of the characteristic featues

Answer 9

Hyper-dense areas in the basal regions of the skull (due to blood build up)

Question 10

What would you see on a lumbar puncture of a patient with SAH?

Answer 10

• Increased opening pressure (because of raised ICP)
• Xanthochromic CSF (lysed blood is evenly mixed in the CSF=> straw coloured CSF) this can only be seen 12hrs after SAH