Strokes Flashcards
What are some common risk factors for strokes
What are the treatment options for an acute srtoke?
What is primary vs secondary prevention of strokes
How do we investigate strokes?
WHat order risk factors: Hypertension Current Smoker Waist-to-hip ratio Diet risk score Not Regular Physical activity Diabetes Alcohol intake Stresst depression Cardiac causes Ratio ApoB to ApoA
Hypertension - 52(%) Not regular Physical Activity 29 Waist to Hip ratio 27 Ratio ApoB to ApoA 25 Current Smoker 19 Diet risk score 19 Cardiac causes 7 Diabetes 5 Stress/depression 5 Alcohol intake 4
Are cholesterol levels responsiable for stroke risk facto?
Not really but ApopB to ApopA IS a relatively big risk factor
What% atheroscolotoc disease? Cardiac Embolism? Small vessel disease? Cryptogenic (unknown)? Haemorrhage?
Crytogenic - 30% Small vessle 25% Cardiac embolism and atherosclerotic cerebrovascular each 20% Haemorrhagic 10-15% Other 5%
What causes a haemorrhagic stroke?
A burst blood vessel
What is Amaloid?
When the blood vessel walls become glass like and so can fracture very easily
Which has worse outlook haemorrhage r ischemic?
Haemmhorage, more likely toresult in death or dependancy
What is a penumbra and when does it occur?
Its the area surrounding th earea of complete ischemia and infaction where the brain tissue gets enough oxygen to survive from other sources for a while but not obtaining enough to keep alive for long
How long in an Ischemic stroke does it take to llose 12km axonal fibres, 13.8 billion synapses and 1.9 million neurons?
1 minute!
What is an ischaemic stroke?
Caused by the occulsion of a vessel
hypoxia - ……….. - …………… - .oedema (swelling) causing further damage)
anoxia - infarction (necrosis)
How long does it take oedema to drecrease?
can be 10 days to a couple f weeks
What happens in the ischaemic cascade?
Hypoxia, anarobic metabolism - lactate released - eventually no more atp - atp pump fails - cell depolarises (NA CA in K out) - Ca triggers glutamate release - more ca into cells - proteases, lipases and free radiclals released due to over excitation
What is the excitotoxicity
Over excitement of the cell due to inappropriate Ca entry causonh extreme lipases, proteases and free radical release
What is released and can increase necrosis on death?
glutamate
Are Stroke symptoms fast onset?
Yes
Common carotid divide into what? How many common carotids do we have?
External and internal common carotids. Usually have 2 carotids (one each side)
How many vertebral arteries? Join to form what?
2 vertebral arteries, joining to form Basilar artery
What area of the brain : Produces speach Listening Comprehension of language speech como vision movement sensations swallowing, breathing, heartbeat, wakefulness, involuntary coordiation
Produces speach - Broca's area Listening - Temporal lobe Comprehension of language - Parietal lobe speech comprehension - Wenicke's area vision - occipital movement - motor cortex sensations - Sensory cortex swallowing, breathing, heartbeat, wakefulness, involuntary - brainstem coordiation - cerebellum
Where does ant cerebral artery supply? Post?
Anterior is more the front (shock horror) and posterior is more the back (wow!)
SIgns and symptoms of stroke?
Motor (clumsy or weak limb) Sensory (loss of feeling) Speech: Dysarthria/Dysphasia Neglect / visuospatial problems Vision: loss in one eye, or hemianopia Gaze palsy
Ataxia/ vertigo / incoordination / nystagmus
Anterior cerebral artery occlusion leads to what?
paralysis of contra-lateral foot and leg
sensory loss over contra-lateral toes, foot and leg
impairment of gait and stance.
Middle cerebral artery occlusion leads to what?
Contra-lateral paralysis of face/arm/leg
Contra-lateral sensory impairment
Contralateral homonymous hemianopia (sees only one side of each eye)
Gaze paralysis to the opposite side
Aphasia if stroke on the dominant (left) side
Unilateral neglect for half of external space if non-dominant stroke (usually right side).
What is aphasia?
Unable to communucate
What is a small vessel stroke?
Lacunar stroke
Devoid of ‘cortical’ signs
E.g. no dysphasia, neglect, hemianopia
Pure motor stroke
Pure sensory stroke
Dysarthria - clumsy hand syndrome
Ataxic hemiparesis
Why do lacunae (small vessel) strokes have such big implications even ifit can be a small stroke?
Because they are in a central area and so affect a large amount of cells/ cell bodies.
Coma, nausea, vomiting, ataxia, drop attacks, vertigo are symptoms of what type of stroke?
Brain stem
TACS PACS, LACS, POCS mean what? What are they all? Highest mortality and recurrence?
TACS = WHole of Middle Cerebral Artery (most of brain), Total anterior circulation stroke PACS = Partial anterior circulation stroke (part of MCA) LACS = Lacunar (small vessel stroke) POCS = Posterior Circulation Stroke
All types of stroke
highest mrotalitity is TAC (60%), then POCS (19), PACS (16) and LACS (11)
Recurrence at 1 year POCS 20%, PACS 17%, LACS 9% and TACS 6%
Is stoke a disease of the elderly?
Yes
risk of stoke is higher in more affluent areas?
No, nearly twice as common in poorer more deprived areas
What is the most important modifiable risk for strokes?
Hypertension!
What modifiable risk factors are there?
Hypertension, smoking, weight, lipids (LDL in conjunction with other risk factors), excessive alcohol intake
When will high cholesterol have an impact?
Yes, high LDL will but only significant when in conjunction with other risk factors
Do smoking and alcohol increase risk factors?
Smoking does, alcohol does but only in excess, a small amount is said to decrease the risk.
Why is high eostrogen related to strokes?
Because it is pro thrombotic
Why would malignancy and genetic factors increase risk of stroke?
Because they can cause a hypercoaguable state
Do stroke units save live? What happens in a stroke unit?
Yes, specialist nurses and staff, they are keen to do scans and prepared to do treatment.
What works well in ischemic stroke?
Asprin
What is Alteplase? WHen best given?
A Thrombolytic agent, best given in the first 4.5 hours
Is IV Thrombolysis time dependant? When is the cut off?
Yes, a dose is goven initially and then a proportion is then given IV over a set time. The cut off is 4.5 hours.
FAST stands for what?
Face
Arms
Speach difficulties
Time
How long to be thrombolysed ?
Within 4.5 hours, after that the risk of harm from bleeding becomes greater than the benefit
Firstr scan of choice?
CT
Specific aditional scans?
Perfusion CT/ Angiogram. If time (which there isn’t) can do MRI/diffusion/perfusion MRIs
What is good about Fast field cycling MRI?
Should be much faster and cheaper esp in the long run. Uses a much lower magnetic field and so potentially safer and shows up areas of infarct very clearly.
What are the pros and cons of MRIs
Quality of photo, but takes time and there are safety issues
WHat s dyarthia?
Slurred speach
Can clot retrieval be used to solve strokes? How does it work?
Yes, studys show that it is more effective than thrombolytic treatment. Basically insert a uninflated balloon past the clot and inflate then drag out the clot.
WHat other treatments are given?
Antiplatelets
Statins
Blood pressure management
Anticoagulation (apixaban, rivaroxaban) - esp if found to have af or other conditions with predispose to thrombosis
