Stroke Flashcards
What is stroke?
Condition characterised by rapidly progressive clinical symptoms and signs of focal, and at times global, loss of cerebral function lasting more than 24hrs or leading to death with no apparent cause other than that
of vascular origin.
What are the two types of stroke? Which is most common?
Ischaemic (70-80%)
Haemorrhagic (20-30%)
How many people have strokes per year in the UK?
152,000
What are the mechanisms of intracerebral haemorrhage?
Charcot Bouchard microaneurysms
Microbleeds
Haemorrhagic transformation of infarcts
Vasculitis
What are the causes of ICH?
Hypertension Trauma Tumour AV Malformation Venous thrombosis Vasculitis Coagulopathy Anticoagulation/TPA Drugs e.g. coccaine Haemorrhagic transformation of infarct
What are the complications of ICH?
Local damage
Local mass effect/herniation
Raised ICP
Hydrocephalus
How is ICH managed?
Imaging/angiography Clotting/platelet function Stop Aspirin/Warfain ICP Management Surgery / EVD Treat risk factors Rehabilitation
What are the two areas around a thrombus called?
Core and penumbra
penumbra has metabolically sensitive neurons
What causes 50% of ischaemic strokes?
Atherosclerosis (10% is carotid)
What causes 25% of ischaemic strokes?
Arteriolarsclerosis
What causes 15% of ischaemic strokes?
Atrial fibrillation and other cardiac emboli
What causes 5% of ischaemic strokes?
Carotid dissection
What are the demographic/non-modifiable risk factors for stroke? (5)
Age Sex (male x1.25) Race (non-white x2) Socioeconomic status (poor) Family history
What are the lifestyle risk factors for stroke? (4)
Smoking (x2)
Overweight (x1.64)
Inactivity (x1.5)
Alcohol (x3)
What are the medical risk factors for stroke? (5)
Hypertension Hypercholesterolaemia Diabetes (x2) Vascular disease (PVD, IHD & CVD) Cardiac (e.g. AF x5, left to right shunts, chamber dilatation)
What are the rare associations with stroke? (5)
Homocysteinaemia Fabrys disease Vasculitis Mitochondrial disease Thromobophilia etc.
Why are statins given for the secondary prevention of stroke?
A decrease of 1mm/L in LDL Cholesterol = 15% risk reduction in ischaemic stroke
Hypertension is a risk factor for stroke. Is this for both systolic and diastolic? What else has been found to make a difference?
Yes for both
Variability on visits to the doctor/hospital (more variation then more risk)
How is stroke classified? (3)
By vascular anatomy (MRI/CT)
By clinical picture (The Oxford Bamford Classification)
By aetiology (the TOAST Classification)
According to the Oxford Bamford Classification, what does a stroke of the anterior circulation present with? (3)
Unilateral motor deficit
Homonymous hemianopia
Higher cerebral dysfunction (e.g. dysphasia, neglect)
According to the Oxford Bamford Classification, what does a stroke of the posterior circulation present with? (4)
Pure hemianopia
Cerebellar signs
Diplopia & CN palsy
Bilateral/crossed sensory-motor signs
According to the Oxford Bamford Classification, what does a lacunar stroke present with? (4)
Pure motor (50%) Sensorimotor stroke (35%) Ataxic hemiparesis (10%) Pure sensory (5%)
What vessels does a lacunar stroke affect?
Small vessels
What tests are done if a patient presents with a possible stroke?
Brain Imaging - CT/MR FBC, and other bloods: ESR, fasting glucose, cholesterol, and VDRL Carotid Doppler ECG +/- 24hr ECG ECHO
What additional tests are done if a patient UNDER 50 presents with a possible stroke?
Vasculitis Screen HIV Test Drug screen Thrombophilia Screen Lumbar Puncture TOE/cECHO Catheter Angiography
What are the first three steps of stroke management?
Consider Thrombolysis
Transfer to Stroke Unit
Review antiplatelet therapy
What are the next two steps of stroke management? (Step 4 and 5)
Address risk factors (diabetes, hypertension, cholesterol, cardiac disease etc)
Treat Complications (nutrition, depression, seizures, DVT, infection, cerebral oedema, pressure sores etc)
What are step 6 and 7 of stroke management?
MDT Rehabilitation (nursing, speech and language, occupational therapy, physio)
Advice & Education (driving, work, weight loss, exercise, smoking, benefits, contraception)
For every 6 patients that receive thrombolysis, 1 benefits.
What is this figure for treatment with aspirin?
What about for acute stroke units?
100
20
What is the % risk of haemorrhage with thrombolysis?
7-8%
What are the current guidelines for antiplatelet therapy?
Aspirin 300mg for 2/52 then Clopidogrel 75mg monotherapy
OR
Aspirin 75mg + Dipyridamole 200mg
What is a TIA?
An acute loss of focal cerebral or monocular function
with symptoms lasting less than 24h and which, after adequate investigation, is presumed to be due to
embolic or thrombotic vascular disease.
OR (new definition):
A transient episode of neurological dysfunction
caused by focal brain, spinal cord, or retinal
ischemia, without acute infarction.
How many stroke patients are suitable for thrombolysis?
20%
How are TIAs managed in A&E?
CT
Doppler/CTA
ECG
Start Antiplatelets
Patients area admitted if…
AF
Carotid stenosis (for surgery)
>2 TIAs in 1 week
With TIA patients, there risk is calculated using the ABCD(2) system. What are the criteria?
Age > 60 = 1 point
BP > 140/90 = 1 point
Clinical features - hemiparesis 2 points, speech 1 point
Duration (10-59 mins 1 point, >1 is 2 points)
Diabetes = 1 point
If their score is >4 they are admitted.
