Stroke Flashcards
what are the two types of stroke
ischaemic haemorrhage
what type of stroke is more common
ischaemic (85%)
what are the two mechanisms of ischaemic stroke
- thrombotic - thrombosis from large vessels e.g. carotid
- embolic - emboli from heart e.g. in AF
definition of a stroke
rapid onset neurological deficit resulting from altered blood supply to brain lasting >24 hours
what is a TIA
transient ischaemic attack due to temporary occlusion of circulation - signs and symptoms last less than 24 hours
what investigation should every patient with TIA get
carotid doppler - thrombosis from carotids most common cause
immediate management of patient who presents with TIA
300mg aspirin
management of patient who has had suspected TIA in last - 7 days - over 7 days ago
if within 7 days – urgent (within 24 hours) assessment if over 7 days – assessment within 7 days
secondary prevention TIA
1st line = clopidogrel
2nd line = aspirin + dipyridamole if patients cannot tolerate clopidogrel
symptoms of stroke/TIA
motor weakness speech problems swallowing difficulty visual field defects balance problems
blood supply to medial + lateral brain
draw circle of willis
what vessels are occluded in total anterior circulation stroke
anterior + middle cerebral arteries
criteria for total anterior circulation stroke
- unilateral weakness +/- sensory loss of arm, leg, face
- homonymous hemianopia
- higher cognitive dysfunction e.g dysphasia
if there is left sided weakness + sensory loss in a TACS stroke, where is the infarct?
RIGHT side of brain
- contralateral to the lesion
what artery is affected in stroke with predominant leg symptoms?
Anterior cerebral
what artery is affected in stroke with predominant arm/face symptoms?
middle cerebral artery
Criteria for partial anterior circulation stroke? (PACS)
2 out of 3 criteria for TACS
- Unilateral weakness +/- sensory loss of arm/leg/face
- homonymous hemianopia
- Higher cortical dysfunction
describe visual field defect in homonymous hemianopia
person only sees half the visual field of each eye
- in left homonymous hemianopia, person cannot see left side of visual field in each eye due to lesion in right occipital lobe/optic tract
what vessels are occluded in posterior circulation stroke? (POCS)
vertebrobasilar arteries
criteria for posterior circulation stroke
any 1 of:
- cerebellar symptoms
- isolated homonymous hemianopia
- loss of consciousness
what artery is affected in lateral medullary syndrome
posterior inferior cerebellar artery
signs of lateral medullary syndrome
ipsilateral horners
contralateral loss of pain/temperature sensations
what is a lacunar stroke?
infarcts around basal ganglia, thalamus and internal capsule
presentations include:
- unilateral weakness +/- sensory loss of leg,arm,face
- pure sensory loss
- ataxic hemiparesis
what is locked in syndrome?
what artery is most commonly affected?
patient is aware + cognitively intact but completely paralysed apart from eye muscles
basilar artery
features of haemorrhagic stroke
loss of consciousness (50%)
headache
nausea + vomitting
seizures (25%)
what imaging is used to differentiate between ischaemic + haemorrhagic stroke
CT
- If negative, rules out haemorrhagic stroke and allows treatment for ischaemic stroke to be started
- may initially be normal in ischaemia – MRI better for infarction
management of ischaemic stroke presenting within 4.5 hours
thrombolysis with IV alteplase
management of ischaemic stroke presenting > 4.5 hours duration of symptoms
300mg aspirin
secondary prevention drugs post ischaemic stroke
aspirin for 14 days
then 75 mg clopidogrel after that (aspirin 75mg + dipyridimole 200mg 2nd line)
statin
secondary prevention ischaemic stroke in AF patient
anticoagulants 2 weeks post stroke
- warfarin or rivaroxaban
what is done 24 hours after administration of thrombolysis
CT to check for haemorrhage (increased risk)
first line radiological invetigation for suspected stroke
CT
what scoring system is used for suspected stroke
ROSIER score
what is webers syndrome
ipsilateral cranial nerve 3 palsy (eye is down + out)
contralateral weakness
lacunar infarcts are stronly associated with what condition
hypertension
