Stroke Flashcards
When do risks of stroke increase?
With age
Public awareness of stroke has been raised using which campaign?
FAST
(Facial weakness
Arm weakness
Slurred speech
Time to call 999)
Define stroke.
Sudden onset of focal or global neurological symptoms caused by ischaemia or haemorrhage lasting more than 24hrs
What % of stroke are ischaemic compared to haemorrhagic?
85% are ischaemic
15% of haemorrhagic
What is meant by a transient ischemic attack?
Sudden onset of focal or global neurological symptoms caused by ischaemia or haemorrhage lasting less than 24hrs
->stroke basically but less than 24hrs
What happens in haemorrhagic stroke?
Blood leaks into brain tissue
What happens in ischaemic stroke?
Clot stops blood supplying an area of the brain
Give some of the common causes of ischaemic stroke.
Large artery atherosclerosis e.g. carotid artery
Cardioembolic
Small artery occlusion
What is the most common causes of a cardioembolic ischaemic stroke?
Atrial fibrillation
What is another name for small artery occlusion?
Lacune strokes
What may a secondary haemorrhagic stroke follow?
Subarachnoid haemorrhage
Arteriovenous malformation
What are some of the non-modifiable risk factors for stroke?
Age
Male
Previous stroke
FH
What are some of the modifiable risk factors for stroke?
Oestrogenic pills (small increase in risks)
HRT (small increase in risk)
Cocaine
Smoking
Poor diet
Diabetes
Hypertension
Atrial fibrillation
What is the most important modifiable risk factor of stroke?
Hypertension
What does chronic hypertension due to vessels?
Exacerbates atheroma and increases the involvement of smaller distal arteries
Small end arteries coming off large arteries experience higher pressure and are more likely to have a lacunar ischaemic stroke or a small vessel haemorrhage.
Which areas of the brain is this more likely to occur?
Brainstem
Basal ganglia
Subcortical areas
How many times more likely are smokers to get a cerebral infarction?
2x more likely
How many times more likely are smokers to get an arachnoid haemorrhage?
3 x more likely
How many times more likely are those with diabetes to develop a stroke?
3 x more likely
What does hypertension, cigarette smoke and diabetes contribute towards in arteries?
Low density lipoprotein deposition in arterial walls
-> risk between development of atheroma in blood vessel walls and stroke
What can drinking small amounts of alcohol do to risk of stroke?
Decreases risks
What can drinking large amounts of alcohol do to risk of stroke?
Increases risk
Who is more likely to get atrial fibrillation?
Those of older age
How many times more likely is someone with atrial fibrillation to develop a stroke?
5 x greater risk of embolic stroke
How does atrial fibrillation link to higher morbidity and mortality of stroke?
Tend to be larger clots leading to more severe strokes
->therefore longer hospital stays
In those with AF, is there any benefit in reducing ischaemic stroke if the patient takes antiplatelets, like aspirin?
No
In those with AF, is there any benefit in reducing ischaemic stroke if the patient takes anticoagulants, like warfarin?
Yes
-> reduces risks by 2/3
Which type of drug have less risk of bleeding than warfarin?
DOACS like edoxaban and apixaban
Which two arteries make up the anterior circulation of the brain?
2x anterior cerebral artery
2x middle cerebral arteries
Which two arteries make up the posterior circulation of the brain?
2 vertebral arteries which join to form 1 basilar artery
In terms of making the diagnosis of stroke, which questions should be asked to work out the type of stroke?
What is the neurological deficit?
Where is the lesion?
What is the lesion?
Why has the lesion occurred?
What are the potential complications and prognosis?
List the functions of the frontal lobe.
High level cognitive function
Memory
Voluntary eye movement
Motor control of speech
Motor cortex
Urinary continence
Emotion and personality
List the functions of the parietal lobe.
Sensory cortex
Sensation
Awareness of parts of the body
Spatial orientation
Ability to perform learned motor tasks
List the functions of the temporal lobe.
Primary auditory receptive area
Comprehension of speech (Wernicke’s)
Visual, auditory and olfactory perception
Learning
Memory
Emotion
Where would the motor homunculus be?
Precentral gyrus
Where would the sensory homunculus be?
Postcentral gyrus
Describe the symptoms of a middle cerebral artery stroke.
Upper limb and facial weakness
Less so leg weakness
Describe the symptoms of a anterior cerebral artery stroke.
Mainly leg weakness
What is controlled by the cerebellum?
Balance and coordination
How many of the 12 cranial nerves arise from the brainstem?
10/12
What could happen if there is a stroke in the brainstem?
Cranial problems on the ipsilateral side
Hemiparesis or arm/leg weakness on contralateral side.
-> contralateral hemiparesis and weakness due to the crossing over of cortical tracts in the medulla
What are the functions of the occipital lobe?
Primary visual cortex
Visual perception
Involuntary smooth eye movement
If you damage one optic nerve, what happens?
Loss of vision/visual changes in one eye, same eye as damaged nerve
Describe the clinical presentation of a stroke.
Sudden onset of symptoms.
Motor issues- clumsy or weak limb
Sensory- loss of feeling
Dysarthria/dysphasia- speech problems
Neglect/visuospatial problems
Vision loss in one eye or hemianopia
Gaze palsy
Ataxia/vertigo
Describe the onset of stroke symptoms.
Rapidly, suddenly
What do stroke symptoms depend on?
Area of the brain affected
Is is normal to have abnormal movements, like a jerk or tremor, after a stroke?
No
Is a severe headache normal after a stroke?
No
If a patient has positive visual phenomena*, what is it more likely to be than a stroke?
*just loads of weird changes to vision as far as I can work out
A migraine
Which classification is used for stroke?
OSCP
What are the four categories of OCSP (Oxford Community Stroke Project Classification)?
TACS
PACS
LACS
POCS
TACS?
Total anterior circulation stroke
PACS?
Partial anterior circulation stroke
LACS?
Lacunar stroke
POCS?
Posterior circulation stroke
Agnosia?
Patient unable to recognize objects, persons or sounds using one or more of their senses.
Anosagnosia?
When patient doesn’t think they’re paralysed when they are
Propsopagnosia?
Inability to recognise faces
Which area of the brain would likely be affected if a person had neglect symptoms like agnosia?
Parietal lobe
Blockage of which types of artery usually causes TACS?
Carotid or middle meningeal
What are the symptoms of TACS?
Complete hemiparesis/numbness
Loss of vision on one side (hemianopia)
Loss of awareness on one side
What are some of the symptoms of POCS?
Loss of balance/coordination
Vertigo
Double vision
Dysarthria
Visual loss
Basilar artery occlusion can lead to one of the worst strokes. Why is this?
Basilar artery supplies brainstem which help us breathe and remain conscious
What can basilar artery occlusion cause to happen in the pons?
Ischaemia in pons
List things which can mimic strokes
(mostly also begin with letter S)
Seizures
Syncope (hypertension)
Sugar (hypoglycaemic or hyperglycaemic) in diabetes
Sepsis and previous stroke
Severe migraine
Space occupying lesions
Vestibular disorders
Demyelination
Transient global ischaemia
Mononeuropathy
Psychological
Migraines give positive symptoms whilst strokes give negative symptoms.
What is meant by positive symptoms?
Excess CNS neurone electrical discharges
Migraines give positive symptoms whilst strokes give negative symptoms.
What is meant by negative symptoms?
Loss or reduction of CNS neurone function
Give some examples of positive symptoms in the following categories:
1. visual
2. somatosensory
3. motor
- Flashing lights, zigzags. lines, objects
- Pain, paraesthesia
- Jerky limb movements
Give some examples of negative symptoms.
Loss of vision
Loss of power
Loss of sensation
So, if there are positive symptoms, it is likely to be a ???
Migraine
And if there are negative symptoms, it is more likely to be a ???
Stroke
Which investigations are carried out for all/most patients with stroke?
Routine blood tests
CT or MRI
ECG + Holter
Carotid doppler stenosis
Why is CT or MRI done in patients with a stroke?
To determine if it’s of haemorrhage or ischaemic cause
Why is an ECG done in someone with a stroke?
Looking for AF and signs of left ventricular hypertrophy
When would you not give a patient thrombolytic drugs?
If they have bleeding in the brain
Which type of imaging is good to show up bleeding in the brain?
CT
What are the three aims of treatment for acute ischaemic stroke?
Restore blood supply
Prevent extension of ischaemic damage
Protect vulnerable brain tissue
Which three symptoms need to be present for a diagnosis of TACS?
Unilateral weakness of the face, arm and leg
Homonymous hemianopia
Higher cerebral dysfunction e.g. dysphasia, visuospatial disorder
Which symptoms must a patient have to be diagnosed with a PACS?
Two of the following:
-Unilateral weakness of the face, arm and leg
-Homonymous hemianopia
-Higher cerebral dysfunction e.g. dysphasia, visuospatial disorder
Which symptoms need to be present to diagnose someone with POCS?
One of the following:
-Cranial nerve palsy and a contralateral motor/sensory deficit
-Bilateral motor/sensory deficit
-Conjugate eye movement disorder e.g. horizontal gaze palsy
-Isolated homonymous hemianopia
Which symptoms would have to be present in order to diagnose a LACS?
One of the following:
-Pure sensory stroke
-Pure motor stroke
-Semsori-motor stroke
-Ataxic hemiparesis
What is the treatment of choice for a large vessel occlusions?
Thrombectomy, removal or the clot in less than six hours
->however, not very realistic as not many patients eligible or will get it done in less than six hours
Even admission to a stroke unit helps with the treatment of stroke.
Name some of the members of the stroke unit team.
Clinical staff
Stroke nurse
Physiotherapists
OT
Speech and language therapists
Dietician
Psychologist
Orthoptist
Which acute stroke treatment has the biggest effect on the individual pateint?
Thrombolysis and thrombectomy
Which acute stroke patient has the biggest effect on the MOST patients?
Stroke unit admission
-> small effect but many more people can benefit from it
Thrombolysis is more effective when?
More effective the quicker it’s given from symptom onset
When should thrombolysis be given?
<4.5hrs
->better to give as soon as possible but must wait an hour to confirm the symptoms are due to stroke
When should thrombolysis not be given?
Blood seen on CT
Recent surgery
Recent episodes of bleeding
Coagulation problems
At which BP levels would it be unsuitable to give thrombolysis?
Systolic > 185
Diastolic > 110
At which glucose levels would it be unsuitable to give thrombolysis?
Less than 2.8 mmol/L
More than 22mmol/L
What is a warning sign of a stroke?
A transient ischaemic attack
->10% of strokes reoccur within first 2 weeks after TIA
What is an effective treatment if there in symptomatic internal carotid artery stenosis?
Carotid endarterectomy
Which drugs can help in the secondary prevention of strokes?
Anti-hypertensives
Anti-platelets
Lipid lowering agents
Which drug should be given in those with AF who have had a stroke to reduce their risks of developing another?
Warfarin
