Stroke Flashcards
Define stroke
Rapidly developing clinical signs of focal (or global) disturbance of cerebral function + lasting > 24h
What are the 3 main aetiological causes of stroke caused by ischaemia?
Thrombosis: MCA branch point, ICA bifurcation
Emboli: AF, rheumatic heart disease
Hypoperfusion
Give the incidence of each type of stroke
Ischaemic 85%
Intracerebral Haemorrhage 10%
SAH 5%
What might cause an emboli leading to stroke caused by ischaemia?
Carotid atherosclerotic plaque breaking off
Atheromatous plaques from heart (ie. AF)
Break off of intima from carotid dissection.
Rarely: venous emboli which passes through the ASD/ VSD
How can hypotension lead to a stroke caused by ischaemia?
If BP below autoregulatory range required to maintain cerebral blood flow, leads to ischaemia in the watershed zones between different cerebral artery territories
List 2 less common causes of stroke caused by ischaemia
Cocaine
Vasculitis
What are the 3 main causes of haemorrhagic stroke?
HTN
Cerebral Amyloid angiopathy
Arteriovenous malformations
List 3 less common causes of haemorrhagic stroke?
Trauma
Tumours
Vasculitis
Summarise the epidemiology of stroke
COMMON
Largest cause of disability
3rd most common cause of death in UK
Usual age of stroke patients: 70+
List 6 presenting symptoms of stroke
SUDDEN-ONSET
Weakness
Sensory, visual or cognitive impairment
Impaired coordination
Impaired consciousness
Head or neck pain (carotid/ vertebral artery dissection)
In a potential stroke patient what do you enquire about?
Time of onset (for emergency Mx if < 4.5h)
Hx of AF, MI, valvular heart disease, carotid artery stenosis, recent neck trauma or pain
What do you look for in a potential stroke patient?
Signs of the underlying cause e.g. AF
Describe the signs seen in lacunar infarct strokes affecting the internal capsule or pons, the thalamus and the basal ganglia
Internal capsule/ pons: pure sensory/ motor deficit (or both)
Thalamus: loss of consciousness, hemisensory deficit
Basal ganglia: hemichorea, hemiballismus, parkinsonism
Describe 2 signs seen in anterior cerebral artery ischaemic strokes
Lower limb weakness
Confusion
Describe the signs seen in middle cerebral artery ischaemic strokes
Facial weakness
Hemiparesis (motor cortex)
Hemisensory loss (sensory cortex)
Apraxia
Hemineglect (parietal lobe)
Receptive or expressive dysphasia (involvement of Wernicke’s + Broca’s areas)
Quadrantopia (if superior or inferior optic radiations are affected)
Describe a sign seen in posterior cerebral artery ischaemic strokes
Hemianopia
Describe 6 signs seen in Posterior Inferior Cerebellar artery ischaemic stroke. In which syndrome is this artery affected?
Vertigo Ipsilateral ataxia Ipsilateral Horner's syndrome Ipsilateral hemisensory loss Dysarthria Contralateral spinothalamic sensory loss Lateral medullary syndrome
Describe 4 signs seen in anterior inferior cerebellar ischaemic strokes
Vertigo
Ipsilateral ataxia
Ipsilateral deafness
Ipsilateral facial weakness
Describe 2 signs seen in basilar artery ischaemic strokes
Cranial nerve pathology
Impaired consciousness
List 5 signs that are seen in multiple lacunar infarct strokes
Vascular dementia Urinary incontinence Gait apraxia Shuffling gait Normal or excessive arm-swing
Describe 6 signs seen in intracerebral haemorrhage strokes
Headache Meningism Focal neurological signs N+V Signs of raised ICP Seizures
What non-imaging investigations do you perform in suspected stroke?
Bloods: FBC. UE, glucose, lipid profile. Clotting profile - check if thrombophilia (esp. in young patients)
ECG: to detect arrhythmias which predispose to emboli
What 5 imaging investigations can you perform in suspected stroke?
Echo: to see cardiac emboli / endocarditis
Doppler carotid US: to exclude carotid artery disease
CT Head: Rapid detection of haemorrhages
MRI-Brain: Higher sensitivity for infarction but less available
CT Cerebral Angiogram: Detect dissections or intracranial stenosis
Describe the management plan for hyperacute stroke
If < 4.5h from onset Exclude haemorrhage using CT-head Thrombolysis IV No aspirin for 24h Monitor on GCS
