L15/16 - stoke and TIA Flashcards
stroke
An abrupt interruption of blood flow to part of the brain, depriving brain tissue of oxygen and nutrients - within minutes, brain cells begin to die
cerebral ischaemic stroke
acute focal neurological dysfunction caused by focal infarction at single or multiple sites of the brain or retina
intacerebral haemorrhage
acute neurological dysfunction caused by haemorrhage within the brain parenchyma or in the ventricular system
mechanisms of ischaemic stoke pathophysiology
embolism
thrombosis
hyperfusion
cardioembolism
A clot can leave the heart and lodge in brain
mechanisms of cardioembolism
- Rhythm abnormalities
- Valvulopathies (valvular disease)
- Pathology in chambers (clots inside chambers)
- Aortic arch (damage in arch and clots can dislodge)
large artery embolism
- atherosclerosis
- > 50% narrowing
- dissection
- mural thrombus
small vessel disease
clots form in small vessels
causes of small vessel disease
hypertension
diabetes
hypoperfusion
- Difficulty with supply of blood to the brain
mechanisms of hypoperfusion
- low systemic perfusion pressure
- cardiac pump failure
aetiology of intracerebrla haemorrhage
- Hypertension
- Vascular malformations (aneurysm, AVN)
- Amyloid angiopathy
- Tumours
- Drug abuse (cocaine)
- Anticoagulant and thrombolytic therapy
- Vasculitis
FAST
face
arms
speech
time
F in FAST
can they move their face?
A in FAST
can they raise their arms?
S in FAST
can they say hello and their name?
T in FAST
time to call 999
common stroke symptoms
- Slurred speech
- Facial droop
- Acute unilateral loss of strength or/and sensation
- Acute monocular or binocular visual loss (complete or incomplete)
- Aphasia
- Ataxia and or vertigo
- Double vision
- Sudden decrease in level of consciousness
ICH treatment
- reverse anticoagulants if taking
- aggressive blood pressure management
- surgical options
within how long should you act on an ICH before it could be fatal
first 6 hours
how to treat a patient with a venous thrombos
blood thinners
example of thrmobolysis treatment
Alteplase
mechanical thrombectomy
- a thin tube is inserted into an artery, usually in the groin
- fed to the site of the clot in or near the brain
- a decide is inserted through the tube to catch the clot and pull it out
thrombolysis
medication it dissolve clot
stentriever
- place stent across occlusion and leave for 10 mins
- reperfuse brain
- most clots will lyse naturally
in which circulation is a thrombectomy more effective
anterior circulation
what % of strokes are due to infarction
85
what % of strokes are haemorrhagic
15
TIA
Neurological Deficit lasting less than 24 hours attributable to cerebral or retinal ischaemia (MINI STROKE)
length of TIAs
most TIAs last under 60mins
causes of TIA
SAME AS STOKE
- Carotid artery disease / large artery disease
- Cerebral small vessel disease
- Cardiac embolism (moving clot)
what % of strokes are preceded by a TIA
20
TIA mimics
- Seizures
- Syncope (loss of consciousness)
- Hypoglycaemia
- Migraine
- Acute confusional states
positive symptoms
flashing lights, limb shaking, tingling…etc
negative symptoms
numbness, drooping…etc
what type of symptoms are observed in a TIA
negative
anterior circulation
internal carotid artery
posterior circulation
vertebral-basilar system
anterior circulation problems
dysphasia
amarausis fugax
amarausis fugax
- Person cannot see out of one of both eyes due to lack of blood flow to eyes
- Cholesterol embolus in retinal artery (come up from carotid artery)
posterior circulation problems
- ataxis if cerebellum involved
- diplopia
- vertigo
- bilateral symptoms if brainstem is affected
how to assess either circulation
- Visual field disturbance (hemianopia)
- Hemiparesis
- Hemisensory loss
paresis
muscular weakness
what is risk of TIA leading to stroke
5% of patients have a stroke after a week
how to score TIA
ABCD2
ABCD2
age BP Clinical features duration symptoms diabetes
age in ABCD2
1 if >60
BP in ABCD2
1 for 140/90
clinical features in ABCD2
2 for unilateral weakness
1 for speech disturbances
duration in ABCD2
- 2 for >60
- 1 for 10-59 mins
- 0 < 10 mins
diabetes in ABCD1
1 yes
0 no
at what score of ABCDE2 do we start to worry
4 - moderate
treatment for TIA
polypill
polypill
combination of:
- statins
- aspirin
- antihypertensives
- folic acid
secondary vascular prevention
carotid endarterectomy
carotid endarterectomy
- removing ulcerated plaque
risk of carotid endarterectomy
- stroke/death 3-5% when opening the artery
- 12th nerve palsy
why can carotid endarterectomy result in death
possibility that the plaque will dislodge and travel to the brain when opening up the artery
why can carotid endarterectomy result in 12th nerve palsu
12th nerve is stretched when surgeon is opening up neck
why is there no point doing aarotid endarterectomy after about 4 weeks
The longer you get away from the time of the TIA, there is a risk
As time goes on, plaques settle and if they have not had a stroke by then, they probably will not have one
most effective medication for TIA
aspirin as stops platelets working
which artery, if occluded, can a surgeon not get to
carotid
