202 Stroke Flashcards
What is the definition of a TIA?
Neurovascular event of cerebral hypoperfusion with symptoms which last <24hrs
What percentage of strokes are ischaemic?
85%
Which artery commonly infarcts in stroke?
Middle cerebral artery
What would a stroke in the left occipital lobe cause?
Right homonymous hemianopia
What would a stroke in the right thalamus cause?
Left hemianaesthesia
What kind of symptoms would an intracranial haemorrhage in the left hemisphere produce?
Right hemiparesis
What is Cushing’s triad?
Sign of raised ICP - suggests cerebral haemorrhage in trauma or a space occupying lesion.
- Change in resps - often irregular or deep
- Bradycardia
- Widening pulse pressure
What are the symptoms of a sub arachnoid haemorrhage?
Sudden thunderclap headache, meningism, loss of consiousness
What are the features of a CVST?
Cerebral venous sinus thrombosis - I.e. DVT of the brain.
Raised ICP
No respect of arterial territories
Usually happens in the young
What is the usual cause of TIAs?
Carotid emboli
What is amaurosis fugax?
Curtain-like loss of vision in one eye due to passage of an embolus through the retinal artery
What is the most modifiable risk factor for stroke?
Blood pressure
What is the ROSIER system?
Recognition of a stroke in the emergency room
Sensitivity >90%, specificity >80%
What is the most common cause of an ischaemic stroke?
Atrial fibrillation causing thrombus in dilated left atrium
What causes stroke in a person with patent foramen ovale?
Valsalva manoeuvre - shunting causing clots to move from right atrium into left atrium
Which circulation is affected given the following symptoms: Amaurosis fugax Aphasia Hemiparesis Hemisensory loss Hemianopia visual loss
Anterior circulation
Which arteries make up the anterior circulation of the brain?
Internal carotids
Anterior cerebral
Middle cerebral
Which arterial system of the brain is affected with any of the following:
Diplopia, vertigo, vomiting Choking and dysarthria Ataxia Hemisensory loss Bilateral visual loss Tetraplasia
Posterior circulation i.e. Vestibulobasilar system
Which arteries make up the posterior circulation of the brain?
Vertebral arteries
Basilar arteries
Posterior cerebral arteries
Posterior communicating arteries
Disease of connective tissue is a predisposing factor for carotid and vertebral artery dissection?
Marfans
Which 5 investigations should be performed when suspecting stroke?
Bloods: FBC, ESR, Glu, Lipids BP ECG CXR Cerebral imaging
What are the specific investigations of a stroke?
6 listed
USS Carotids
CT/MRI angiography or venography
Catheter angiogram
What is the initial treatment for an ischaemic stroke?
Thrombolysis <3 hours post onset of symptoms
What are the 5 causes of ischaemic stroke?
Thrombus Large artery stenosis Small vessel disease Cardio embolic Hypoperfusion
What are the 2 types of haemorrhagic stroke?
Intracranial haemorrhage
Subarachnoid haemorrhage
What is ischaemic penumbra?
e.g. In stroke where the infarcted region is surrounded by a swollen area which does not function but is structurally intact - regain of function happens when there is neurological recovery
What is the cause of neuronal cell death in a stroke?
Hypoxia leading to fall in ATP with release of glutamate which opens up calcium channels with release of free radicals.
Leads to inflammatory damage, necrosis and apoptotic cell death
Where is stroke typically seen?
Infarction in internal capsule following thromboembolism in middle cerebral artery branch
What are the clinical features of a thromboembolus in the right middle cerebral artery?
Left limb weakness develops over seconds/mins/hours
Contralateral hemiplegia/hemiparesis with facial weakness
Aphasia
Extensor plantar response
What are lacunar infarcts?
Small infarcts seen on CT/MRI/autopsy Causes: Pure motor stroke Pure sensory stroke Sudden unilateral ataxia and sudden dysarthria with clumsy hand
Definition of ataxia?
Loss of full control of body movements
Define aphasia
Inability to nudist and or produce speech
Define dysarthria
Difficult or unclear articulation of speech that is otherwise linguistically normal
Define dysphagia
Difficulty/discomfort swallowing
Define hemiparesis
Paralysis of one side of the body
What is papilloedema a sign of?
Encephalopathy
Define: hemianopia
Blindness over half the field of vision
What is alteplase?
Recombinant tissue plasminogen activator - it generates plasmin which is one of the key enzymes of fibrinolytic pathway. Increased activity causes hyperfibrinolysis
What is the long term management for a stroke?
Identify and address R/F:
Antihypertensive Rx
Antiplatelet Rx - long term aspirin/clopidogrel
Anticoagulants - heparin/warfarin when there is AF
Rehabilitation
What are the risks of using anticoagulants such as heparin and warfarin too soon following an infarction?
Risk of provoking cerebral haemorrhage
Why is physio important in the first few weeks following stroke?
Reduce spasticity
Prevent contractures
Teach use of walking aids
What is the 2 year mortality of a stroke?
25%
Is early mortality more common in thromboembolitic or haemorrhagic strokes?
Haemorrhagic
What are the surgical options for treatment of stroke?
Carotid endarterectomy
Stenting of carotids
