30. Stroke: Presentation and Investigation Flashcards
How old are most stroke patients?
60+
What is stroke?
- sudden onset of loss of neurological function and deficit
- lasts more than 24 hours
- of vascular origin
- result from ischaemic infarction or bleeding into part of the brain with rapid onset of CNS signs and symptoms
How to differentiate between stroke and transient ischaemic attack?
- stroke lasts for more than 24 hours
- transient ischaemic attack lasts less than 24 hours and its effects are only temporary
What are symptoms of stroke? (5)
- loss of power and movement
- loss of sensation (part of body feels cold/ dead)
- loss of speech and comprehension
- loss of vision
- loss of coordination
What history aspects need to be considered? (6)
- time of onset
- witnesses +observations
- headache/ vomiting/neck stiffness/ photophobia (suggests haemorrhage)
- loss of consciousness
- fit
- inconsistence
What neurological related loss of function signs are seen on taking history and examination in stroke patients? (7)
- motor (clumsy or weak limb)
- sensory (loss of feeling)
- speech (dysarhria (slurring of speech or not articulating)/ dysphasia (not comprehending))
- neglect ( visuospatial problems)
- vision ( loss in one eye, or hemianopia)
- gaze palsy
- ataxia/vertigo/incoordination/ nystagmus (loss of control of body movements)
What causes a stroke? (7)
- small vessel occlusion/ cerebral angiopathy/ thrombosis in situ (damage to brain due to blockage of blood due to thrombus or embolus)
- cardiac emboli
- atherothromboembolism
- CNS bleeds (trauma, aneurysm rupture, anticoagulation, thrombolysis) due to rupture of blood vessels
- disease of vessel wall
- rupture of vessel wall (haemorrhage)
- disturbance of normal properties of blood
What makes blood vessels more fragile and more susceptible to stroke?
hypertension (makes vessels weaker)
What is meant by penumbra?
area in the brain not getting enough oxygen, is asleep/dead and needs blood flow restored to it otherwise tissue will die
In which arteries of the brain are clots most likely to appear in?
Most likely to appear in middle cerebral arteries
What do external carotid arteries supply?
the face
What do internal carotid arteries supply?
anterior portion of the brain
How should a link between vessel obstruction and stroke be made?
signs and symptoms of the patient should make sense; fit with an artery territory and an area of the brain (e.g. if numb left leg then numb left arm), if if doesn’t fit together then problem most likely is function rather than caused by stroke
What do the carotid systems mainly supply? (2)
- most of the hemispheres
- cortical deep white matter
What does the vertebro-basilar system supply?
-brain stem
- cerebellum
- occipital lobes
(posterior aspects of the brain)
What are 2 main vascular supplies in the brain?
- carotid system
2. vertebro-basilar system
Where does Broca’s area sit and what does it do?
- sits at the frontal and parietal lobes joining
- area of speech formation
What part of the brain is most likely affected if person doesn’t understand speech AND cannot form speech?
most likely a bigger portion of the brain; e.g. cerebrum or both frontal and parietal lobes affected
What is the most likely location of problem if patient cannot move or feel anything and has weakness everywhere?
most likely problem is closer to mid-brain as it affects brain fibres extending to many brain locations (small stroke in midbrain can result in major deficit as fibres packed close together in mid-brain)
What percentage of strokes are as a result of:
- infarction
- haemorrhage
- 85% infarction (ischaemic)
- 15% haemorrhage (haemorrhagic)
What are the main causes of ischaemic (infarction) stroke; 85%? (5)
- large artery atherosclerosis (e.g. carotid)
- cardioembolic (AF)
- small artery occlusion
- undetermined/ cryptogenic
- rare causes: arterial dissection or venous sinus thrombosis
What are the main causes of haemorrhagic stroke; 15%? (2)
- primary intracerebral haemorrhage
2. secondary haemorrhage e.g. subarachnoid haemorrhage or arteriovenous malformation
What is meant by haemorrhagic stroke?
haemorrhage/ blood leaks into brain tissue and puts pressure on surrounding vessels
What is meant by ischaemic stroke?
clot stops blood supply to an areas of the brain (obstruction/infarction)