stroke- presentation Flashcards
whats the commonest cause of long term disability in the uk?
stroke
how many NHS beds to people who have had strokes occupy?
20%
what is a stroke?
neurological deficet of sudden onset lasting more than 24 hours
what are stroke symptoms?
Loss of power
Loss of sensation
Loss of speech
Loss of vision
Loss of coordination
what part of the body does stroke effect?
brain- due to a blockage of a blood vessel by thrombus or embolus
what part of the brain is supplied by the carotid system?
most of the hemispheres and cortical deep white matter
what part of the brain does the vertebro basilar system supply?
brain stem, cerebellum and occipatl lobes
whats the function of the sensory cortex?
pain, heat and other sensations
whats the function of tge temporal lobe?
hearing, intellectual and emotional functions
whats the function of the parietal lobe?
comprehension of language
whats the function of the occipital lobe?
primary visual area
whats the function of wernicke’s area
speech comprehension
whats the function of the cerebellum
coordination
whats the function of the brainstem?
swallowing, breathing, heartbeat, wakefulness centre and other involuntary functions
whats the function of the frontal lobe?
smell, judgement, foresight and voluntary movement
whats the function of broca’s area?
speech
what causes a stroke?
blockage of a vessel with thrombus or clot
disease of vessel wall
distrubance of normal properties of blood
rupture of vessel wall
whats the commonest cause of cardioembolic stroke?
atrial fibrillation
what part of the brain can be affected by a stroke?
left or right
carotid territory or vertebrobasilar
cerebral hemispheres or brainstem
cortex or deep white matter
what would a brainstem stroke be?
wether the lesion is in the brainstem
what would a cortical stroke be?
wether there is a lesion in the cortex
what would a lacunar stroke be?
if the lesion is in the deep white matter
what example of lesion would be unilateral field loss?
left optic nerve compression
what example of lesion would be bitemporal hemianopia?
chiasmal compression from pituitary tumour
what example of lesion would be homonymous hemianopia?
left cerebrovascular event
what are characteristics sof total anterior circulation TACS?
20% of strokes
patient usually has weakness, sensory deficit homonymous hemianopia
higher cerebral dysfunction
what are the characteristics of partial anterior circulation? PACS
35% strokes
2 of 3 TAACS criteria or restricted motor/sensory deficit
what are caracteristics of lacunar strokes? LAC
20% strokes
pure motor (commonest) complete or incomplete weakness of 1 side
pure sensory
sensory symptoms, same distribution
sensorimotor
combination of the above
ataxic hemiparesis
hemiparesis and ipsilateral cerebellar ataxia
small infarcts in basal ganglia or pons.
intrinsic disease of single basal perforating artery
what are charactristics of posterior circulation? POCs
25% strokes
affecting brainstem, cerebellar or occipital lobes
frequently complex presentation, may include bilateral motor/sensory deficit disordered conjugate eye movement isolated homonymous hemianopia ipsilateral cranial nerve palsy with contralateral motor/sensory deficit coma disordered breathing tinnitus vertigo Horner’s
what type of stroke has the highest mortality at one year?
TACs
what type of stroke has the smallest mortality at one year?
LACs
what type of stroke has the highest recurring rate at one year?
POCs
risk factors for stroke
Modifiable
High blood pressure
Atrial fibrillation
Non-modifiable
Age
Race
Family history
what are the investigations for stroke?
blood tests: full blood count, lipids
ECG
what imaging would you use for stroke?
CT scan
MRI scan
carotid doppler
whats better a CT or mri snd why?
CT
Quick
Shows up blood
MRI scan
Takes up to 30 minutes
Claustrophobic
Shows up ischaemic stroke better that CT does
how can you harm someone with a stroke?
Alteplase
Cause unexpected bleeding either in the brain if tissue has established damage
If brain tissue already dead restoring blood supply is not going to help
Or bleeding elsewhere (e.g. Gut)
whats the first thng a patient with a stroke should have to treat?
0.9 mg/kg intravenous rt-PA
should patients with suspected stroke have priority over others for ambulance etc?
yes
contraindications to thrombolysis?
Age
Most RCTs have excluded those under 16 and over 80 yrs
Licence currently limited to <80yr
Stroke outcomes worse anyway in over 80s
Greater age perceived as greater risk of bleeding
Lots of case series reporting good outcomes in older patients treate
what surgery would you do for a patient that has had a stroke?
thrombolysis
what is the majority age of stroke patients?
over 65
how do you tell the difference between haemorhage and infarct on a scan?
in a ct scan, black image is infarct as there is more fluid
white image is haemorrhage
how often is a stroke ischaemic and how often is it haemorrhage?
85% ischaemic
15% haemorrhage
whats the difference between haemorrhage stroke and ischaemic stroke?
haemorrhage/blood leaks into brain tissue
ischaemic: clot stops blood supply to an area of the brain
what are the main causes for ischaemic strokes?
large artery atherosclerosis
cardioemboic (atrial fibrilation)
small artery occlusion
