Subarachnoid Haemorrhage Flashcards
Define subarachnoid haemorrhage
Arterial bleeding into the subarachnoid space
Subarachnoid - pia mater
What are the causes of subarachnoid haemorrhage
Rupture of intracranial saccular aneurysm (80%), usually at the circle of Willis
Perimesencephalic haemorrhage i.e. parenchymal haemorrhages tracking onto surface of brain (10%)
Arteriovenous malformations , bleeding diatheses, vertebral or carotid artery dissection with intracranial extension, mycotic aneurysms, drug abuse (cocaine amphetamines)
What are the risk factors of subarachnoid haemorrhage
Polycystic Kidney disease
Hypertension
Smoking
Excess Alcohol
Saccular aneurysms: polycystic kidney disease, Marfan’s syndrome, pseudoxanthoma elasticum, Ehlers-Danlos syndrome, Moya Moya disease, HIV/AIDS, TB
What are the the symptoms of subarachnoid haemorrhage
Severe headache (Sudden-onset, “Hit on the back of the head with a bat”)
Vomiting, nausea
Confusion
Neck stiffness
Photophobia
Decreased level of consciousness, coma
Seizure
What are the signs of subarachnoid haemorrhage on examination
Meningism: Neck stiffness, Kernig’s sign (resistance of pain on knee extension when hip is flexed) due to irritation of the minges, pyrexia
Focal neurological signs: Usually develop on second day and are caused by ischaemia form vasospasm and reduced brain perfusion. Ophthalmoplegia caused by pressure on cranial nerves
GCS may be reduced
Signs of ICP: papilloedema, Iv or III cranial nerve palsy. HTN and bradycardia
Subhyaloid haemorrhage on fundoscopy (rare)
Investigations for subarachnoid haemorrhage
- URGENT CT, non-contrast
- If CT is normal and → 12 hours after onset LP
Bedside: ECG
Blood: clotting
Other:
- CT head: Hyperdense areas in the basal regions of the skull (due to blood in the subarachnoid space) | Hyper-attenuating material pooling within the occipital horns of the lateral ventricles
- LP: Increase opening pressure, increased RBC, reduced WCC, xanthochromia (confirmed by spectrophotometry of CSF supernatant after centrifugation
- MRI/CT: Detects the source of bleeding, Done if the patient is a candidate for surgery
Digital subtraction catheter angiography (DSA): gold standard
What is the management for subarachnoid haemorrhage
- A-E assessment, consider intubating and ventilation
- Urgent CT scan
- Urgent neurosurgical and intensive care referral
- Analgesia: paracetamol, codeine, tramadol, morphine, oxycodone (Avoid aspirin and NSAIDs)
- Stool softener and anti-emetic, tranexamic acid, IV mannitol/hypertonic saline
- Maintain normovolaemia and avoid hypovolaemia - control BP with nimodipine to prevent stroke
- Compression stockings and intermittent compression
- Neurosurgery or interventional radiology
What neurosurgical interventions are used for subarachnoid haemorrhage
radiology: coiling (usually platinum) of the aneurysm
Surgery: craniotomy, clipping of the aneurysm
What are the complications of subarachnoid haemorrhage
Neuropsychiatric problems e.g. cognitive impairment
Chronic hydrocephalus → shunt placement
SIADH → hyponatraemia
Neck injury → spinal cord damage (More common in high impact trauma e.g. high-speed road traffic collisions)
Spinal cord injury (SCIWORA): damage to the spinal cord without damage to bony structures
What is the prognosis for subarachnoid haemorrhage
Children with severe traumatic brain injury can make a good physical recovery, though the period of rehabilitation may be long
SAH is associated with trauma, infection, and vascular abnormalities, and it requires high levels of care during management and after discharge.
When identified in a timely manner, the outcomes for patients with SAH are more favourable
May develop cognitive, behavioural, and mental health problems
Differentials for subarachnoid haemorrhage
Venous sinus thrombosis
Cocaine use
arterial dissection
Arteriovenous malformation
Vasculitis
Sickle cell disease
Trauma
