Condition-Subarachnoid Haemorrhage Flashcards
Describe the layers of meninges and what a subarachnoid haemorrhage is…
Meninges:
- Skulls cap
- Epidural Space
- Dura Mater
- Subdural Space
- Arachnoid mater
- Subarachnoid space
- Pia Mater
SAH: Arterial Haemorrhage into subarachnoid space
What is the most common cause of a SAH?
Berry Aneurysms- a rupture of a saccular aneurysm at the base of the brain (85%)
Other causes: arteriovenous malformations, vertebral artery dissection
List some risk factors that predispose people to SAH…
- Hypertension
- Smoking
- Alcohol
- Bleeding disorder
- Increased risk berry aneurysms
List some risk factors for developing Berry Aneurysms…
- Polycystic kidney disease
- Coarction of the aorta
- Marfan’s syndrome
- Ehlers-Danlos syndrome
- SLE
Where is the most likely place for Berry Anerysms to occur?
Between the junctions of vessels in the circle of Willis. Most common is the anterior cerebral/ anterior communicating junction
Descibe the presenting symptoms of a patient with SAH…
- Sudden onset worst headache- typically occipital = THUNDER CLAP HEADACHE
- Nausea/ vomitting
- Collapse
- Seizures
- Reduced consciousness
- meningism symptoms:
- Neck stiffess
- photophobia
List some of the signs of SAH on physical examination…
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)
Which investigations could you do to identify SAH?
-
Imaging: CT scan
- Bedside: BP, HR, GCS
- Bloods: FBC, U&Es, ESR/CRP, clotting
- Angiography: detect source of bleeding
- Lumbar puncture: If CT-ve
What sort of haemorrhage can be seen in this CT? Describe some of the characteristic featues
Hyper-dense areas in the basal regions of the skull (due to blood build up)
What would you see on a lumbar puncture of a patient with SAH?
- 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