Subarachnoid Haemorrhage

Question 1

Define Subarachnoid Haemorrhage?

Answer 1

Arterial Haemorrhage into the subarachnoid space

Question 2

What are the causes of SAH?

Answer 2

85% - Rupture of a saccular aneurysm at the base of the brain (Berry Aneurysms)
10% - Perimesencephalic Haemorrhage
5% - Arteriovenous malformations, bleeding diathesis, verterbral artery dissection

Question 3

What are the Risk Factors for SAH?

Answer 3

Hypertension
Smoking
Excess Alcohol Intake

Question 4

What are saccular aneurysms are associated with?

Answer 4

Polycystic Kidney Disease
Marfan’s Syndrome
Ehlers-Danlos Syndrome

Question 5

What are the epidemiology of SAH?

Answer 5

Incidence: 10/100,000

Peak Incidence: 40s

Question 6

What are the presenting symptoms of SAH?

Answer 6

Sudden-Onset worst headache ever 
Nausea/vomiting 
Neck stiffness
Photophobia 
Reduced LoC

Question 7

What are the signs of SAH on physical examination?

Answer 7

Meningism
GCS -check for deterioration
Signs of Raised ICP
Focal Neurological signs

Question 8

What are signs of Meningism?

Answer 8

Neck Stiffness
Kernig’s Sign
Pyrexia

Question 9

What are the signs of raised ICP?

Answer 9

Papilloedema
IV or III nerve palsies
Hypertension
Bradycardia

Question 10

What are the bloods you would do for SAH?

Answer 10

FBC
U&Es
ESR/CRP
Clotting

Question 11

Why do we do CT scans in SAH?

Answer 11

Hyperdense areas in the basal regions of the skull (due to blood)

Question 12

Why do we do Angiography for SAH?

Answer 12

Detect source of bleeding

Question 13

Why do we do Lumbar Puncture for SAH?

Answer 13

Increased opening pressure
Increased red cells
Xanthochromia - straw-coloured CSF due to breakdown of RBCs