Subarachnoid Haemorrhage

Question 1

SAH

Why do most SAH’s happen?

Answer 1

secondary to a Berry aneurysm

Question 2

SAH

Typical presentation

Answer 2

• thunderclap headache

Question 3

SAH

Describe the headache and associated symptoms

Answer 3

thunderclap
- nausea and vomiting
- photophobia
- visual disturbances

Question 4

SAH

What is it usually triggered by?

Answer 4

exertion or sexual activity

Question 5

SAH

What are some classical signs of someone who has had a SAH?

Answer 5

• reduced GCS
• meningism
• pyrexia
• signs of raised intracranial pressure (i.e. hypotension, bradycardia and papilloedema)

Question 6

SAH

How is it diagnosed?

Answer 6

CT

Question 7

SAH

CTs can miss a SAH. What other investigation can be done?

Answer 7

lumbar puncture

Question 8

SAH

When does a CT scan become less reliable with picking up a SAH?

Answer 8

with time
(sensitivity of a CT scan is 95% at day 1, 74% at day 3, and 50% at day 7)

Question 9

SAH

The diagnostic findings on an lumbar puncture are:

(2)

Answer 9

• blood in the CSF
• xanthochromia

Question 10

SAH

What is xanthachromia and why does it occur?

Answer 10

the yellowing of CSF 12 hours after exposure to air, due to the breakdown of haemoglobin into bilirubin

Question 11

SAH

Why might these investigations also be done?

• Routine blood tests (FBC, U&Es)
• Coagulation screen and group and save/crossmatch
• ECG

Answer 11

• Routine blood tests (FBC, U&Es) – to rule out another medical cause of the headache, and especially infective causes, as there is a significant overlap between the clinical features of SAH and meningitis
• Coagulation screen and group and save/crossmatch – these should be done in anticipation of future procedures and potential surgery.
• ECG – ST elevation is a sign of SAH, and SAH can cause dangerous arrhythmias.

Question 12

SAH

In a severe presentation, how do we manage a pt?

Answer 12

A-E approach

Question 13

SAH

In a severe presentation, how do we try and reduce cerebral ischaemia?

Answer 13

calcium channel blocker nimodipine is used to reduce vasospasm

Question 14

SAH

In a severe presentation, what do we do if pt has a reduced GCS?

Answer 14

intubation

Question 15

SAH

What drugs are used to reduce intracranial pressure?

Answer 15

Mannitol and inotropes

Question 16

SAH

An important emergency complication is Cushing’s reflex.

What is that? Why does it happen? What can it precede?

Answer 16

• the triad of raised blood pressure, brady**cardia and reduced respiratory rate
• occurs as a result of raised intracranial pressure in the context of head injury
• can precede brainstem herniation.

Question 17

SAH

How do we treat Cushing’s reflex?

Answer 17

The treatment is to lower the raised ICP.

Mannitol and inotropes

Question 18

SAH

How is it medically managed after A-E approach?

Answer 18

supportively
- analgesia (headache)
- anti-emetics (vomitting)
- nimodipine (maintain bp)
- IV saline

Question 19

SAH

What should be arranged to assess for any causative aneurysms?

What would first-line treatment be?

Answer 19

Angiography
- first-line treatment would be endovascular coiling of the aneurysm.

Question 20

SAH

What is the most common cause of a painful 3rd nerve palsy ?

Answer 20

enlarging unruptured posterior communicating artery aneurysm

Question 21

SAH

Following major SAH, there is neck stiffness and a positive ____ sign

Answer 21

Kernig’s