Stroke and TIA Flashcards
what is a stroke
rapid development of symptoms/signs
focal loss of cerebral function
global loss with coma or SAH
lasts > 24 hours
presumed vascular origin
what are the 2 types of stroke
ischaemic stroke
haemorrhage stroke
what is shown in the image
ischaemic stroke, left
haemorrhage stroke, right
how does an ischaemic stroke happen
artherosclerosis causes a thick, rough deposit to form on the inner wall of an artery blocking the passage way or narrowing it
only small amount of blood can get through
OR: a blood clot gets stuck in an artery and blocks the blood flow
how does a haemorrhage stroke happen?
blood from burst artery is forced into the tissue of the Brian (intracerebral haemorrhage) or into the narrow space between the brain surface and the layer of tissue that covers the brain (subarachnoid haemorrhage)
intra-cerebral haemorrhage
bleed form a blood vessel
variable prognosis
occasionally from an AVM or tumour
how does infarction occur
thrombosis in situ
thrombus forms at site of a hardened patch of artery within the brain
usually affects the small blood vessels in the brain
how does infarction occur
thrombosis in situ
thrombus forms at site of a hardened patch of artery within the brain
usually affects the small blood vessels in the brain
main risk factors for thrombosis in situ
hypertension
smoking
lipids
embolic stroke
thrombus forms outside the brain and embolisms to the brain
main risk factors for embolic stroke
atrial fibrillation
cardiac failure
valvular disease
diabetes
lipids
what is a TIA
transient ischaemic attack
acute loss of focal cerebral function
or
acute monocular visual loss (amaurosis fugax)
lasts <24 hours but mostly short lived
scheme for noticing signs of stroke
FAST
f- face
a- arms
s- speech
t- time
what is the scale used in stroke assessment
ROSIER
recognition of stroke in the emergency room
what is the ROSIER scale
in acute stroke rapid intervention is crucial to maximise early treatment benefits
validated scoring system to identify patients with acute stroke from myriad other non stroke condiotns would be helpful
what does the image show
ROSIER scale
taking stroke history
time of onset of symptoms
parts of the body affected
nature of symptoms, positive or negative
accompanying symptoms
previous TIA.stroke
past medical history (vascular)
family history
lifestyle
questions to ask if patient has suddenly..?
risk factors for stroke and TIA
age
family history
smoking
alcohol
recreational drugs
hypertension
diabetes
raised cholesterol
ischaemic heart disease
peripheral vascular disease
atrial fibrillation
classification of stroke
anterior (carotid) system
posterior (vertebrobasillar) system
common stroke symptoms for the middle cerebral artery
parietal, frontal, superior temporal lobes
contralateral
UMN facial weakness
hemiplegia (arm > leg)
hemianopia
aphasia (dominant)
visuospatial problems (non- dominant)
PARTIAL SYNDROMES ARE COMMON
common stroke syndrome for vertebral and basilar arteries
brain stem & cerebellum
diplopia, disorders of eye movements
nystagmus, vertigo, vomiting
dysarthria, dysphagia, bulbar weakness
ipsilateral LMN facial weakness
respiratory failure, coma
contralateral hemiparesis, quadriparesis
what is the Bamford classification
The Bamford classification divides people with stroke into four different categories, according to the symptoms and signs with which they present. This classification is useful for understanding the likely underlying pathology, which in turn gives information on treatments likely to be useful and the prognosis. It is a relatively simple, robust, bedside classification using clinical information.
rankin scale
alteplase
known as r-tPA
no other thrombolytic is licensed for intravenous thrombolysis in acute stroke
how is alteplase administered
each box contains 2 bottles
1 with the rug in powdered form
1 sterile water for injections
1 transfer canula to dissolve the drug
calculate the dosage from patients weight
draw up 10% of the normal dose into 10ml syringe and give as slow IV push over 1 minute
draw up 90% into 50ml infuse over 1 hour
limitations of IV rtPA
generalisability
major strokes are difficult
increased risk of sICH with larger stroke
what if IV thrombolysis is ineffective
consider intra-arterial therapies
age < 60
major stroke with proven proximal middle cerebral artery thrombus on Ct angiography
no sign of rapid improvement with IV thrombolysis
rapid transfer to RVI neurosciences
request Ct head and CTA in patients younger than 60 with signs of major stroke
intra-arterial therapies
intra-arterial clot removal
intra-arterial thrombolysis
recanalisation actuellement ischemic stroke
endovascular treatment
contraindication to IV rtPA
no change in NIHSS score one hour following administration of IV rtPA
3 hour treatment window has expired but less than 10 hours
severe neurological deficits in NIHSS > 16
treatment within 8 hours longer in some cases such as posterior circulation
IV/IA rtPA
merci retrieval device
penumbra aspiration device
endovascular treatment
femoral or radial access
series of catheters: sheath, guide catheter, micro catheter
wire navigation
