Stroke Flashcards
what is the incidence of stroke in the uk?
110,000 per year
costs 7 billion£
outline what a stroke is symptomatically
sudden onset over minutes with progression:
- weakness, speech problems, swallowing problems, visual problems
why is stroke important to prevent
1 out of 6 people die in hospital
1/3 of survivors need help for activities of daily living
what is the mechanism of a stroke
problem with blood supply to the brain / cerebral circulation
what are the two types of stroke
ischaemic
haemorrhagic
what is an ischaemic stroke
a ‘blockage’
85% of strokes are ischaemic
atheroma + thrombus on top
embolism
what does ischaemia mean
lack of blood supply, in this case due to blockage of vessel
what is a haemorrhagic stroke
a ‘bleed’
15 % of strokes are haemorrhagic
atheroma casues rupture
less often aneurysm
how does a CT scan show a bleed in the brain
bright white blob
what are the causes of arterial disease?
age
hypertension
diabetes (obesity)
hyperlipidaemia (obesity)
smoking
blood clots can also come from the heart and cause ischaemic stroke (cardioembolism)
if a man had a stroke and cannot move right side of the body which side is the stroke likely to be on?
left side
what is anterior and posterior circulation?
posterior is vertebrobasilar affecting the cerebellum (coordination), occipital lobe (vision), parietal lobe (sensation)
anterior is carotid and affects the temporal lobe (langauge) and frontal lobe (movement)
which area is likely to be affected by the stroke if the patient can follow instructions and understand the doctor but cannot speak words to make sense?
brocas aphasia
anterior circulation affecting the temporal lobe on the left hand side
why do we need to get people affected by stroke to hospital quickly?
confirm it is a stroke
consider emergency treatment
admit patient to stroke unit for specialist care
what is the UK FAST
face
arms
speech
time
campaign for the onset signs of stroke
what is wrong with the UK FAST campaign
recognises 70% of strokes
wrongly infers all patients will have same symptoms
many other neurological conditions can cause these symptoms
what things can be wrongly thought to be a stroke
seizures
syncope
severe migraine
can an ischemic stroke be seen on a CT scan early on?
no the CT can look normal and the infarct will develop and be visible later
why is intravenous thrombolysis administered to ischaemic stroke patients
unblocks artery to activate bodies own blood clot removal system and restore blood supply/circulation
but only suitable for 15% of stroke patients
what does current evidence say about the benefits of intavenous thrombolysis administration?
chance of favourable outcome decreases with time - evidence shows treatment is beneficial up to 4.5 hours after stroke onset
why is intravenous thrombolysis sometimes dangerous
3% of patients get bleeding from the treatment in the brain area affected by the stroke
what is a more severe stroke with a blocked main artery called
large vessel occlusion
what is a thromborectomy
surgical operation
guide wire is inserted into wrist and fed up to the brain to cerebral arteries and grabs thrombus (blood clot) to remove it
when should a thromborectomy be performed?
<6 hours since stroke started
it is complex
what % of stroke patients are suitable to a thromborectomy
only 10%
and they are only available in regional neuroscience units
what is an CT angiogram
dye injection to visualise blood circulation
what is usually visualised on CT angiogram
circle of willis
how has AI helped with strokes?
AI assistance for thromborectomy
helps identify large vessel occlusion on a CT angiogram
guides to find where the clot is
this information helps decide most beneficial treatment
evaluates perfusion images
what is a haematoma
blood located outside of blood vessles
what can be used in treatment of haemorrhagic stroke
intravenous blood pressure lowering drugs to reduce haematoma expansion
‘pro-clotting’ injection (TRANEXAMIC ACID) may have a role in the future
so in summary what are the 3 main treatments that should be considered for a stroke patient
for ischaemic stroke - intravenous thrombolysis
for ischameic stroke due to LVO - mechanical thromborectomy
haemorrhagic stroke - control blood pressure
what are some blood biomarkers helpful in the identification of stroke type
haemorrhage = HIGH glial fibrillary acidic protein (GFAP)
LVO = HIGH D-dimer (blood clots) or LOW glial fibrillary acidic protein (GFAP)
what is the RADAR study
rapid assay diagnostic for acute stroke recognition
outline the RADAR study
cohort study to determinate diagnostic accuracy of new portable test to support identification of LVO and haemorrhage
1. LVOne finger prick test - 2 lateral flow assays read in 12 minutes for D-dimer and GFAP.
results for this study are yet to come out
