Stroke Flashcards
What are key features of a stroke? (5)
sudden onset focal symptoms loss of brain function last >24hrs neurological problems due to vascular disease
1/3 of all stroke presentations are stroke mimics. True/false?
True
What are 5 main stroke mimics?
seizure (mostly) sepsis toxic/metabolic Space-occupying lesions presyncope
The Rosier Score helps determine if patient is having a stroke. With Score >0 = stroke is likely and score 0 = stroke is unlikely. What scores you -1 and what scores you +1?
-1: loss of consciousness or syncope
+1: asymmetric facial weakness, asymmetric arm weakness, asymmetric leg weakness, speech disturbance, visual field defect
What is the 3 types of stroke in order to most common to least? (85%, 10%, 5%)
Infarct
Haemorrhage
Subarachnoid haemorrhage
What are 3 types of haemorrhagic strokes?
structural abnormality (e.g. arterio-venous malformation) hypertensive amyloid angiopathy (protein deposition that makes brain more likely to bleed)
What are 3 common types of infarcts in order of most common to least?
artheroembolic arteries
cardioembolic
small vessel (due to damage over time)
What is the most common cause of cardioembolic infarct?
atrial fibrillation
What are the investigations for stroke?
CT first
Infarcts appear white/dark on CT and haemorrhages appear white/dark.
infarct - dark
haemorrhage - white
Which appears sooner on CT scan - infarct/haemorrhage?
haemorrhage
What is a hyperacute sign of stroke visible on CT?
artery occlusion - static blood will show up as bright white
What type of infarcts are difficult to pick up on CT and so MRI is used?
posterior circulation infarct (lots of bony interference)
tiny infarct
The key sequence used in MRI for showing infarcts is Diffusion Weighted Imaging and is then compared to ADC map. How long are MRIs sensitive to infarcts for after the infarct has occurred?
10 days
Why is it difficult to differentiate an infarct and haemorrhage on CT when scan is done 1 week or more after the stroke?
Because CT is not sensitive for blood after 1 week so area will appear dark
What are 7 steps to the acute management of stroke?
thrombolysis/thrombectomy, imaging, swallow assessment, nutrition and hydration, antiplatelets, stroke unit care, DVT prevention
What is the substance in thrombolysis that causes clot breakdown?
Recombinant tissue plasminogen activator
How long do you have to thrombolyse patient from onset of stroke for it to be beneficial?
4.5hrs
What are some factors to consider when deciding whether to thrombolyse or not?
age (older more likely to bleed) time since onset previous intracerebral haemorrhage or infarct atrophic changes BP (hypertensive) diabetes
What is the risk of bleeding with thrombolysis?
5%
What are the overall recanalisation rates of IV tPA?
40-50%
What scoring system is used for assessing severity of stroke?
NIHSS
What dose of aspirin after stroke?
300mg
What must you do before giving aspirin to stroke patient?
CT to check its not a haemorrhage
How long do you wait after thrombolysis to give aspirin?
24hrs
In case of mild stroke (NIHSS <3) what treatment do you give and for how long after the stroke?
clopidogrel and aspirin
for 3 weeks
What is used in stroke patient to prevent DVT & what patients is this contraindicated in?
intermittent pneumatic compression
contraindicated in peripheral arterial disease, leg ulcers
If symptoms last less than ___hrs, it is a TIA and if they last more than ___hrs it is a stroke.
24hrs
A TIA is a benign process and does not cause ischaemic damage to the brain. True/false?
False
It causes long term ischaemic damage & increases your risk of having a minor stroke
What are the investigations for TIA?
carotid imaging to look for carotid artery stenosis,
ECG,
blood tests
What is the treatment for TIA?
medication: antiplatelets (aspirin) & statins
consider carotid endartectomy
If systolic blood pressure is >150mmHg in patients with primary intracerebral haemorrhage or >185mmHg in patients for thrombolysis what is treatment?
Medication for 7 days to lower systolic BP to 140mmHg
often IV GTN
15% of ICH is associated with anticoagulation. What is mortality rate from ICH?
30-50%
What is the treatment for anticoagulant reversal for warfarin, direct thrombin and factor Xa inihibitors?
warfarin: vitamin K/prothrombin complex
direct thrombin +
factor Xa inhibitors: prothrombin complex
What are types of embolism in stroke?
Cardiac embolism (Atrial fibrillation, ventricular aneurysm, endocarditis) Paradoxical embolism Atherosclerotic embolism Fat embolism Air embolism
What are 2 types of thrombosis?
Perforator thrombosis: lacunar infarct
Acute plaque rupture with overlying thrombosis
What are 3 causes of ischaemic stroke?
Embolism, thrombosis & arterial dissection
Difference between Wernickes area and Broca’s area and aphasia
wernickes area responsible for formulating what were going to say and Broca’s area executes the plan by activating the vocal apparatus in motor cortex,
so wernicke’s aphasia
So wernicke is the writer of the play in the back and broca is the expressive actor on stage
Where is Broca’s area exactly?
left frontal lobe
Where is Wernicke’s area exactly?
Left temporal lobe
Broca’s aphasia?
Expressive aphasia - difficulty in getting words out and forming the words, able to comprehend speech of others when its simple grammatically
Wernicke’s aphasia?
No difficulty producing speech, sentences normal grammatically but sentences are incoherent, struggle to understand other people or written word - is essentially language comprehension area
What is the most common location for a ruptured berry aneurysm causing subarachnoid haemorrhage?
anterior communicating artery and anterior cerebral junction
What can be detected in CSF from lumbar puncture after subarachnoid haemorrhage?
xanthochromia - bilirubin pigments
What arteries are most commonly involved in lucanar infarcts?
lenticulostriate arteries (branches of the middle cerebral arteries) that feed the basal ganglia
Gerstmann came from AFAR?
Agraphia, Finger agnosia, Acalculia and Right-left confusion - a lesion of dominant inferior parietal lobe supplied by middle cerebral artery
Subdural haematoma presents how on CT
crescent-shaped haemorrhage, crosses suture lines - can present with headache and gradual dementia
Epidural haematoma presents how on CT
bi-convex haemorrhage, doesn’t cross suture lines - can present with lucidity and then loss of consciousness, CN palsies and hemiparesis - much more acute
PICA - posterior inferior cerebellar artery syndrome presentation?
sensory deficits of trunk and extremities on opposite side of infarction, sensory deficits of face and CN on ipsilateral side. Loss of pain and temp on contralateral side of body and ipsilateral side of face. also dysphagia, swallowing problem, ataxia
Lesion of lateral part of medulla
