Stroke Flashcards
Define stroke
Clinical syndrome consisting of rapidly developing clinical signs of focal disturbance of cerebral function lasting more than 24hrs or leading to death with no apparent cause other than a vascular origion (WH)
What is the prevalence of stroke?
- More than 100,000 strokes in the UK per year
2. 4th biggest killer in UK, 2nd in world
Are strokes more prevalent in men or women?
1 in 6 men
1 in 5 women
What is the average age for strokes?
72 for men, 78 for women
Most likely to have a stroke after 55, but 1/4 happen to people of working age
Describe ischaemic strokes (3)
- Clots form in brain’s blood vessels and block flow to brain cells
- Occur in a brain artery or small blood vessel deep in brain
- Account for 80% of strokes
Give the classifications and percentages of ischaemic strokes (4)
- Large vessel disease 50%
- Small vessel disease 30%
- Cardioembolic 20%
- Cryptogenic/rarities 5%
Describe haemorrhagic stroke (3)
- Blood vessel in the brain breaks/ruptures
- Blood seeps into brain tissue causing brain cell damage
- 20% of strokes
What is the most severe type of stroke?
Haemorrhagic
Generally associated with a considerably higher risk of dying within the first 3 months
What are 2 types of haemorrhagic stroke?
Primary intracerebral haemorrhage (bleeding from blood vessel inside brian) Subarachnoid haemorrhage (bleeding from blood vessel into he subarachnoid space)
What are 2 causes of haemorrhagic strokes?
- High blood pressure
2. Brain aneurysms (weakness or thinness in blood vessel)
What causes arterial ischaemic stroke?
- Atheroma (affects mainly large and medium sizes arteries)
(Blood clot blocks flow of blood and oxygen when they form here)
What is atheroma?
- Degeneration of the artery walls caused by fatty deposits and scar tissue
- Leads to restriction of the circulation and a risk of thrombosis
What are 6 causes of atheroma/narrowing of the arteries?
- Smoking
- High blood pressure
- Obesity
- High cholesterol levels
- Diabetes
- Excessive alcohol intake
What are 5 risk factors of high blood pressure?
- Being overweight or obese
- Excessive alcohol intake
- Smoking
- Lack of exercise
- Stress
What are 7 non-modifiable risk factors of stroke?
- Age
- Ethnicity
- Gender
- Family history of heart disease
- PFO (hole in heart)
- Diabetes (type 1)
- Atrial fibrillation
What is atrial fibrillation?
Irregular and abnormally fast heart rate
What is the FAST acronym?
Face
Arms
Speech
Time (act quickly)
Describe F of FAST acronym
Face may droop to one side and may not be able to smile
Describe A of FAST acronym
May not be able to lift both arms because of weakness or numbness in one arm
Describe S of FAST acronym
Speech may be slurred and problems in understanding
What are 8 other symptoms of stroke?
- Complete paralysis on one side of body
- Sudden loss or blurry vision
- Dizziness
- Confusion
- Problems with balance/co-ordination
- Dysphagia
- Severe headache
- Loss of consciousness
What are the symptoms of a stroke in the dominant hemisphere?
Language dysfunction: expressive aphasia, receptive aphasia, dyslexia and dysgraphia
What are the symptoms of a stroke in the non-dominant hemisphere?
- Anosognosia: neglect of paralysed limb, denial of weakness
- Visuo-spatial dysfunction: geographical aphasia, dressing apraxia, constructional apraxia
What are the symptoms of a stroke in either hemisphere?
- Hemiparesis
- Hemisensory loss
- Visual field neglect
What investigations are used to diagnose stroke?
- Blood tests
- CT head or MRI brain scan
Heart and blood vessel tests: - ECG (echocardiogram)
- Carotid ultrasound
What is the prognosis of stoke?
- 30 day case fatality: 20%
Give the percentages for the symptoms which may remain at 6 months
Hemiparesis 50% Cognitive deficit 50% Hemianopia 20% Aphasia 20% Sensory deficits 20%
What are the 2 strongest predictors of outcome in stroke?
- Severity (degree of neurologic impairment and size/location of infarction)
- Patient age
What 2 factors can improve outcome?
- Opening up blocked vessel early
2. MDT care on a dedicated stroke unit
Give 5 interventions for ischaemic strokes
- Thrombolysis
- Thrombectomy
- Carotid intervention
- Cholestoral lowering
- Long-term blood pressure lowering
What is thrombolysis? (3)
- Injecting alteplase to dissolve blood clots and restore blood flow to the brain
- As soon as possible after stroke - not recommended if more than 4.5 hours have passed
- Only used in ischaemic, can worsen haemorrhagic
What is thrombectomy? (3)
- Emergency treatment used for a small proportion of ischaemic stroke
- Inserting catheter into large artery in brain to remove clot through suction
- Most effective ASAP
What is carotid intervention?
Unblocking the carotid artery in the neck if ischaemic stroke is caused by narrowing of this artery
How is cholesterol lowered? (5)
- Using statins (medicine) to reduce future vascular events
- Lower plasma LDL cholesterol
- Inhibit cholesterol production in the liver
- Stabilise atherosclerotic plaques
- Have anti-inflammatory properties
How is blood pressure lowered in the long-term at discharge?
- Antihypertensives such as ACE inhibitors, thiazide diuretics, calcium channel blockers
What are 3 interventions for haemorrhagic stroke?
- Medication to lower blood pressure and prevent future strokes
- Surgery (craniotomy)
- Surgery for hydrocephalus
What does surgery involve in haemorrhagic strokes?
- Craniotomy involves removing blood from the brain and repairing burst blood vessels
- Surgery for hydrocephalus (complication) involves using a shunt to drain CSF from the ventricles of the brain
