L 42 Flashcards
What does FAST stand for?
What % of strokes are FAST symptoms present for?
Face, Arm, Speech, Time
85% of strokes show FAST symptoms.
Strokes generally affect … year olds.
They can occur in … people but mainly in … people.
… have a higher risk than …
There is a … stroke rate in NZ Europeans
The stroke rate has … for māori, pacific and some asian populations.
Strokes generally affect >65 year olds.
They can occur in younger people but mainly in older people.
Females have a higher risk than males (as they live longer)
There is a declining stroke rate in NZ Europeans
The stroke rate has doubled for māori, pacific and some asian populations.
Māori and pacific people are … times more likely to suffer a stroke than NZ europeans. Their strokes are likely to be … severe and occur at a … age
Māori and Pacific people are 1.5-3 times more likely to suffer a stroke than NZ Europeans. Their strokes are likely to be more severe and occur at a younger age
Main risk factors for stroke x4
Increasing age
Female gender
Non-European ethnicity
HIGH BLOOD PRESSURE
Other risk factors (more general) x7
Obesity, smoking, heart disease, inactivity, stress, alcohol
Having a stroke significantly … your risk of having a recurrent stroke
…
What is a stroke?
An interruption of blood flow to the brain, causing neurons to become damaged from a lack of oxygen.
What artery supplies blood to the brain?
The internal carotid artery
What artery supplies blood to the face, scalp and ears?
External carotid artery
What is a global stroke?
When blood flow is interrupted to most of the brain
What is a focal stroke?
When blood flow is interrupted to a specific area of the brain.
Every minute that a stroke is untreated, the average patient loses…. x3
What is the neuron lss equivalent to?
1.9 million neurons
13.8 billion synapses
12km of axonal fibres
Neuronal loss is equivalent to 3.6 years of aging.
Th salvageable tissue … over time that a stroke is left untreated
Th salvageable tissue decreases over time that a stroke is left untreated
Territories of the 3 main arteries
Anterior cerebral arter (ACA)
Middle cerebral artery (MCA)
Posterior cerebral artery (PCA)
Symptoms of a left MCA stroke
On the right side: Weakness, sensory loss
Difficulty speaking and understanding speech
Dysarthria
Difficulty speaking
Aphasia
Difficulty understanding speech
The left side of the brain controls the … side of the body.
The right side of the brain controls the … side of the body.
The left side of the brain controls the right side of the body.
The right side of the brain controls the left side of the body.
Symptoms of a right MCA strokee
Left sided: weakness, sensory loss
Neglect (to a body part), can’t recognise own condition, flat mood/depressive moods
Asomatognosia
Failure to recognise parts of one’s own body
Anosognosia
Patient is unaware of their illness
Benefits of stroke management?
20% better survival rates regardless of age, gender, stroke type
2 examples of stroke management
Dedicated stroke units in urban centres (e.g coronary care)
Telehealth for rural areas (e.e telestroke)
What are the 2 types of stroke and their prevalence?
Haemorrhagic stroke: 15%
Ischaemic stroke: 85%
What are the colloquial names for haemorrhagic and ischaemic strokes?
Bleed (haemorrhagic)
Block (ischaemic)
What happens in a haemorrhagic stroke?
A break in a blood vessel of the brain (aneurysm) causing an area of bleeding in the brain
What happens in an ischaemic stroke?
What are the 2 types of ischaemic stroke?
A blood clot or fatty plaque blocks blood flow in the brain.
The 2 types of ischaemic stroke:
1. when the clot forms in the brain = thrombotic stroke
2. when the clot forms elsewhere in the body and and travels to the brain = embolic stroke
Main cause of thrombotic stroke
Atherosclerosis
Where would an embolic stroke likely travel from?
The neck (carotid artery) Or the heart (atrial fibrillation)
How do you know where and what kind of stroke a patient has?
Brain imaging: CT and MRI scan
What does the NIH stroke scale assess?
What are some elements that it evaluates?
Severity of stroke, appropriate treatment and predicts patient outcomes.
Elements: visual, motor, sensory, coordination, speech, understanding.
What does a higher score on the NIHSS mean?
A score >16 predicts …
A score <6 indicates…
A 1 point increase on the scale … the possibility of a positive outcome by 17%
Higher score: more severe stroke
A score >16 predicts strong probability of death
A score <6 indicates strong possibility for a good recovery
A 1 point increase on the scale decreases the possibility of a positive outcome by 17% (higher score = worse outcomes)
Acute treatment for ischaemic stroke (overview + example)
What time period gives the most long term benefit?
Second line?
Reperfusion therapy (thrombolysis) to restore circulation and limit extent of brain damage e.g Alteplase is first line - MOST BENEFIT WITHIN 4.5 HOURS Scond line = tenecteplase
Which 2 drugs are commonly confused and caution must be taken to not confuse them?
Alteplase (tPA)
Tenecteplase (TNK, a tPA)
What benefit does alteplase treatment produce if used within 4.5 hours?
A 30% greater chance of a good outcome at the 3 month mark if treated within 4.5 hours.
Eligibility for first line thrombolysis if patient is/has: x4
- Age 18-85
- Ischaemic stroke diagnosis
- Symptoms within 4.5 hours
- Patient able to undergo CT scan before administration (to check what kind of stroke they have)
Exclusion criteria for thrombolysis
- Patient in coma
- Non-diasbling stroke symptoms
- Hx of stroke w/in 12 weeks
- MI w/in 30 days
- Conditions involve risk of bleeding
- Thrombocytopenia
Limitations of thrombolysis
- Short window (need to have access to hospital care within this time)
- Success depends on size, type and location of stroke
- If clot 8mm+ then<1% chance of reperfusion therapy working.
What is a neurointervention in terms of stroke?
Thrombectomy via a catheter through the groin and up into blood vessels to remove the clot mechanically.
Guidelines for neurointervention
Eligible patients: IV thrombolysis while arranging and endovascular thrombectomy.
Acute treatment for haemorrhagic stroke is dependent on the … and …
It aims to control.. x4
Haemorrhagic stroke treatment is dependent on the cause and the severity of the bleeding.
It aims to manage or control:
Bleeding, seizures, blood pressure, intracranial pressure (ICP)
High pressure in the intracranial cavity can cause …
Dropping a patients blood pressure will cause ….
High pressure in the intracranial cavity can cause a seizure.
Dropping a patients blood pressure will cause less bleeding (less force pushing it out)
What does ICH mean?
Clinical guidelines for haemorrhagic stroke treatment
ICH: intracranial haemorrhage
Guidelines:
1. Patients with ICH due to oral anticoagulants should urgently receive a specific reversal agent
2. Blood pressure need to be reduced to systolic 140mmHg (but not lower as this will cause reduced blood flow in itself)
3. Surgical evacuation not recommended for patients with a bleed above the supratentorial region in the cerebellum
Transient ischaemic attack (TIA)
Sometimes known as a …
…/… patients will have a stroke within a week following a TIA.
Is this a medical emergency?
A ministroke that presents in the same way as a stroke but symptoms resolve within 24 hours.
AKA a warning stroke.
1/12 patients will have a stroke within 1 week following a TIA.
Yes this is a medical emergency (indicates a high risk of stroke) - FAST rules apply
Treatments to reduce risk of stoke:
Antiplatelets
Cholesterol lowering agents
Blood pressure control
Anticoagulants
Examples of antiplatelets
Aspirin, clopidogrel
Examples of anticoagulants
Warfarin, dabigatran, rivaroxaban
