Stroke Flashcards
Two main pathological processes which lead to stroke?
Infarction
Haemorrhage
Aetiology of infarction?
Emboli (cardiac or carotid)
Thrombosis
Hypotension, e.g. in sepsis
Main cause/risk factor for haemorrhagic stroke?
Hypertension
Which functional areas of the brain are affected infarctions in the territory of:
a) anterior cerebral
b) middle cerebral
c) posterior circulation
d) small vessel
a) motor cortex, frontal lobe
b) motor cortex, somatosensory cortex, parietal lobe, optic radiations (causing quadrantanopia)
c) occipital lobe, cerebellum, cranial nerves
d) pons, internal capsule, thalamus, basal ganglia
Signs which indicate intracerebral haemorrhage rather than infarction? (4)
Headache, meningism, nausea and vomiting, seizures
Main investigation in suspected stroke?
Urgent brain imaging (CT or MRI) to exclude haemorrhage
Indications for thrombolysis?
Patient is within 4.5hrs of symptoms onset, aged 18-80 years and no contraindication exists (e.g. haemorrhage on CT)
Agent used for thrombolysis, and dose?
recombinant tissue plasminogen activator e.g. alteplase 0.9mg/kg over one hour
When should antiplatelets be used? What agent?
In acute ischaemic stroke where haemorrhage has been excluded. Aspirin 300mg
Which investigation is essential to carry out as soon as possible?
Formal swallow assessment
Who should be considered for carotid endarctectomy?
Patients with non-disabling stroke/TIA, if carotid artery is found to be stenosed on carotid Doppler ultrasound +/- CT/MRI angiography
Tool which can be used to assess suspected stroke?
ROSIER
Stroke mimics? (7)
Hypoglycaemia Migraine Space occupying lesion Post-ictal Intracerebral haemorrhage Bell's palsy Non-organic/functional
Which antiplatelets are used in secondary prevention?
Aspirin and dipyridamole
When should warfarin be used for anticoagulation?
In patients with risk of venous embolism e.g. with persistent/paroxysmal AF, prosthetic valves
Prognosis of a stroke which presents with loss of consciousness?
Poor prognosis, however LOC is an uncommon presentation of stroke
Contraindications to thrombolyis? (2)
Recent stroke within 3 months
Current haemorrhagic stroke
Gait abnormality in stroke?
Hemiplegic gait- steps are slower and leg is dragged in an arc
What clinically defines large vessel occlusion in stroke?
Loss of higher cortical functions e.g. speech, personality
Investigations aimed towards finding the underlying cause of a stroke? (5)
Basic bloods esp lipids and glucose
ECG- atrial fibrillation, signs of previous ischaemia, left ventricular hypertrophy
Carotid artery Doppler
Holter monitoring
Echocardiogram- atrial dilatation if longstanding A fib
Definition of stroke?
Acute onset of a focal neurological deficit due to obstruction of blood flow to the brain
Small vessel (lacunar) stroke is usually caused by what process?
Thrombosis (rather than emboli)
Symptoms which should raise suspicion of stroke?
Unilateral weakness which is initially flaccid
Unilateral sensory loss
Homonymous hemianopia
Dysphasia
Definition of TIA?
Sudden onset of focal neurological deficit lasting less than 24 hours
What score is used to stratify stroke risk in patients who have had a TIA?
ABCD2 score
A= age B= blood pressure C= clinical features D= diabetes mellitus D(2)= duration of symptoms
Prevention of stroke in patients with TIA? (2)
Clopidogrel 300mg loading dose, followed by 75mg daily
Control of BP/lipids/diabetes
In cardio-embolic stroke, when should anticoagulation be commenced and what is the rationale behind the delay?
14 days. Reduces risk of haemorrhagic transformation
