Subarachnoid Haemorrhage Flashcards
1
Q
What is a subarachnoid haemorrhage?
A
Spontaneous bleed into the subarachnoid space, often catastrophic (type of haemorrhagic stroke).
2
Q
What are the causes of a subarachnoid haemorrhage?
A
- Berry aneurysm rupture (80%)
2. Arterio-venous malformations (15%)
3
Q
Where do Berry aneurysms most commonly occur?
A
Junctions:
- Posterior communicating artery with ICA
- Anterior communicating artery with ACA
- Bifurcation of the MCA
4
Q
What are the risk factors for a subarachnoid haemorrhage?
A
- Previous aneurysmal SAH, family history
- Smoking, alcohol, HTN, hypercholesterolaemia
- Polycystic kidney disease, aortic coarctation, Ehlers-Danlos syndrome
5
Q
What are the signs and symptoms of a subarachnoid haemorrhage?
A
- Sudden onset excruciating headache, occipital, thunderclap.
- Vomiting, collapse, seizures, coma
- Neck stiffness, meningism (after 6 hours), retinal haemorrhage, focal neurology.
6
Q
What are the important differentials for a subarachnoid haemorrhage?
A
- Meningitis
- Migraine
- Intracerebral bleed
- Dissection of carotid or vertebral artery
7
Q
What investigations are carried out for a suspected subarachnoid haemorrhage?
A
- Urgent CT
- Consider LP if CT-ve, wait >12 hours to allow for haemolysis, see yellowing of CSF
- 3 different red cells counts, compared 1st and 3rd
8
Q
What is the management for a subarachnoid haemorrhage?
A
- Refer to neurosurgery immediately
- Re-examine CNS, BP, pupils, GCS
- Maintain cerebral perfusion, maintain systolic at <160
- Nimodipine 60mg QDS (Ca antagonist)
- Analgesia for headache
- Surgery
9
Q
What are the complications of a subarachnoid haemorrhage?
A
- Re-bleeding commonest cause of death (first few days)
- Cerebral ischaemia commonest cause of morbidity (vasospasm)
- Hydrocephalus
10
Q
What is the prognosis of subarachnoid haemorrhage?
A
- 25% die within 1 month
2. 50% left with long-term neurological deficit
