Cerebrovascular accident (STROKE) Flashcards
What are the main types of stroke?
- Ischaemic
- Haemorrhagic- splits into intracerebral haemorrhagic and subarachnoid haemorrhagic
What percentages of occurrence of each type of stroke?
- Ischeamic- 85%
- intracerebral haemorrhagic- 10%
- Subarachnoid haemorrhagic- 5%
What is a transient ischaemic attack (TIA)?
An acute loss of focal cerebral or ocular function with symptoms that last LESS than 24 hours (symptoms usually resolve within minutes to a few hours)>
What is the difference between the two types of haemorrhage stroke?
- Intracerebral hemorrhage- is when blood vessels bleeds into the deep cerebral tissue of the brain
- Subarachnoid haemorrhage- when a blood vessel on the surface of the brain bleeds into the subarachnoid space
What is the difference in incidence of strokes between black and white people?
Black people are almost 2x more likely to have a stroke
What are the risk factors for ischaemic stroke?
smoking
alcohol use
inactivity
poor diet
hypertension
cardiac disease e.g. atrial fibrillation, heart failure
dyslipidaemia
diabetes
migraines
increasing age
Male
family history of TIA or stroke
Previous stroke/TIA
What are the risk factors for haemorrhagic stroke?
Hypertension
male
smoking/drugs
diabetes
anticoagulant use
head injury
What are some of the causes of an ischaemic stroke?
- Atherosclerosis
- Carotid embolism
- Arterial stenosis
- Hypercoagulable stress
- Arterial dissection
- Vasoconstriction associated with substance misuse
What are some of the causes of a intracerebral haemorrhagic stroke?
- Hypertension
- Vessel abnormalities
- Bleeding disorders
- Vasculitis
- amyloid angiopathy
- Arteriovenus malformations
What are some of the causes of a subarachnoid haemorrhagic stroke?
- Aneurism- congenital or due to high blood pressure
- Arteriovenous malformations
What is atrial fibrillation?
AF is a cardiac arrhythmia in which the atria contract rapidly but not all pulses are passes from the atria to the ventricles by the AV node. This leads to irregular and incomplete contraction.
This causes turbulent blood flow and blood stasis in the heart which increases the risk of an embolus formation
What is a haemorrhagic transformation?
A haemorrhagic transformation can occur in up to 6% of ischaemic stroke patients and is when patients will suffer an ischaemic stroke and then also a brain haemorrhage
What are the factors that increase risk of a haemorrhagic transformation?
- If the ischaemic stroke was cardioembolic
- The larger the infarct size
What is the difference between arterial thrombosis and an arterial embolism?
- Arterial thrombosis- when a thrombus forms in an artery that supplies the brain with blood and oxygen. this is commonly caused by atherosclerotic plaques that rupture, leading to the formation of clots
- Arterial embolus- Thrombus/debris accumulates at a site away from the brain. Then a part or all of this is dislodged and travels to the brain and forms a blockage.
What is an arterial thrombosis?
- Arterial thrombosis- when a thrombus forms in an artery that supplies the brain with blood and oxygen. this is commonly caused by atherosclerotic plaques that rupture, leading to the formation of clots
What is an arterial embolism?
- Arterial embolus- Thrombus/debris accumulates at a site away from the brain. Then a part or all of this is dislodged and travels to the brain and forms a blockage.
What is a TIA?
Transient ischaemic attack
- Is like a mini stroke
- Similar symptoms but they resolve quickly
Symptoms of an ischaemic stroke
- Weakness- can affect half of the body, or all (more rare- paresis)
- Loss of sensation in one side of body
- Facial droop
- Blindess
- Dysarthria- difficulty articulating words
- Ataxia- failure of muscle coordination
- dysphagia
- confusion
- headache
What does FAST stand for?
FACE weakness, can they smile?, is it droopy
ARM- can they raise both arma
SPEECH- can they speak clearly, do they understand
TIME- call 999
What is important regarding medication/nutrients in a suspected stroke patient?
All suspected stroke patients should be made ‘NIL by mouth’ until they have had a SALT assessment (should be within 4 hours of admission)
Why is brain imaging important in determining a stroke?
CT scan can determine between an ischaemic and a haemorrhagic stroke
- In a haemorrhagic stroke- we wouldn’t want to give thrombolysis or aspirin
What tests need to be done on the arrival of a stroke patient?
BP, oxygen sat, temp
Blood glucose- symptoms may be related to hypoglycaemia?
Clotting- APTT, INR- determine bleeding risk
ECG- determine any arrythmias
Fasting lipids-likeliness of atherosclerois
Blood culture- infection?
FBC- thrombocytosis? leukaemia?
urea and electrolytes
How is the severity of the stroke determined?
Using NHS stroke scale (NHSSS)
SCORES:
0 = no stroke
1-4= minor
5-15 = moderate
16-20 = moderate-severe
21-42 = severe
What is the immediate treatment for a patient with a TIA or minor stroke WITHOUT AF, within 24 hours of onset?
Dual anti-platelet therapy:
Clopidogrel 300mg STAT
Aspirin 300mg STAT
- Then 75mg of each OD for 14 days
Consider PPI
- Then, clopidogrel 75mg OD monotherapy (long-term antithrombotic)
For those that are not appropriate for dual antiplatelet, including those outside 24 hours of onset – clopidogrel 300mg STAT followed by 75mg OD
