Sub-arachnoid haemorrhage Flashcards
What is the definition of a sub arachnoid haemorrhage?
Spontaneous arterial bleed into the subarachnoid space
How common are sub arachnoid haemorrhage?
Annual incidence of 6 per 100,000
Mean age of presentation is 50 years old
What is the pathophysiology of a sub arachnoid haemorrhage?
- Berry aneurysms are most common at the bifurcations/branches of the arteries/Circle of Willis
- Most asymptomatic until they rupture
- Some become symptomatic due to mass effect
What are the risk factors/aetiology of sub arachnoid haemorrhage?
- Rupture of berry/saccular aneurysms
- Congenital arteriovenous malformations
- Hypertension
- Atherosclerosis
- Cocaine
- ↑ alcohol
- Trauma
- Genetics
- Family history
What are the signs/symptoms of a sub arachnoid haemorrhage?
- Painful 3rd nerve palsy – due to mass effect
- Sudden onset of severe ‘thunderclap’ occipital headache – reaches maximum intensity within minutes
- Nausea/vomiting
- Seizures
- Sometimes loss of consciousness/dizziness
- Neck stiffness – sign of meningeal irritation
- +ve Kernig’s sign – sign of meningeal irritation
- Focal neurological signs
- Papilloedema
What diseases present similarly to sub arachnoid haemorrhage?
- Tension headache
- Migraine
- Stroke
- Meningitis
What investigations are carried out for a suspected sub arachnoid haemorrhage?
- CT – as soon as possible
- LP – when strong clinical suspicion of sub arachnoid haemorrhage but CT is normal
- ↑ bilirubin/oxyhaemoglobin which leads to a red/brown colouration
- Must be performed at least 12 hours after symptoms
- MR angiogram
- ECG
- Ophthalmoscopy = intraocular haemorrhages
What are the surgical treatments for a sub arachnoid haemorrhage?
• Obliteration of the aneurysm by surgical clipping/insertion of a fine wire coil
What are the pharmacological treatments for a sub arachnoid haemorrhage?
- Nimodipine (Ca channel blocker)
- Saline fluids – counteract hyponatraemia
- Antihypertensive - prevention
What are the non pharmacological treatments for a sub arachnoid haemorrhage?
- Bed rest
- Supportive measures
- Smoking cessation - prevention