Subarachnoid Haemorrhage

Question 1

What is Subarachnoid Haemorrhage?

Answer 1

• A bleed in the subarachnoid space between the arachnoid mater and pia mater

Question 2

What are the Causes of Subarachnoid Haemorrhage?

Answer 2

• Traumatic (SAH) : Head injury (fall, assault, road traffic collision)
• Spontaneous: rupture of a cerebral aneurysm, arteriovenous malformation, arterial dissection, vasculitis, tumour, drugs (cocaine), SCD

Question 3

What are the Modifiable Risk Factors for SAH?

Answer 3

• Hypertension
• Smoking
• Alcohol Abuse
• Substance Misuse

Question 4

What are the non-modifiable risk factors for SAH?

Answer 4

• Sex - female
• Race - Japanese/ Finnish
• FHx of Aneurysms
• Genetic Predispositions - Autosomal Dominant PCKD, type IV Ehlers-Danlos Syndrome

Question 5

What is the Anatomy of the brain?

Answer 5

• Three meningeal layers: dura, arachnoid and pia
• Neuroanatomy: Meninges, Circle of Willis, Aneurysm location

Question 6

What forms the Circle of Willis?

Answer 6

• Carotid System
• Vertebrobasilar System

Question 7

What are some of the Aneurysm Location?

Answer 7

• Saccular/ Berry Aneurysms located at the branching points of the major blood vessels

Question 8

What are the Clinical Features of SAH?

Answer 8

• Thunderclap or Sudden-onset headache (maximum intensity within seconds)
• Headache associated with photophobia and neck stiffness
• Nausea and Vomiting
• Third Nerve Palsy
• Reduced Consciousness
• Diplopia
• Ptosis

Question 9

What are the two classic signs of meningism?

Answer 9

• Kerning’s Sign
• Brudzinski’s Sign

Question 10

What is the Kernig’s Sign?

Answer 10

• inability to fully extend at the knee when the hip is flexed at 90 degrees due to pain

Question 11

What is the Brudzinski’s Sign?

Answer 11

• Spontaneous flexion of the knees and hips on active flexion on the neck due to pain

Question 12

What is a third nerve palsy?

Answer 12

• A SAH or enlarging cerebral aneurysm is associated with a third nerve palsy
• Double Vision
• Eye is down and out
• Ptosis
• Pupillary Dilatation
• Loss of light reflex

Question 13

What does the involvement of the pupils means?

Answer 13

• Parasympathetic motor fibres associated with the pupillary light reflex are situated superficially within the nerve
• Compressive lesions (aneurysms) will affect fibres to pupillary dilatation and loss of light reflex