Stroke - clinical and presentation Flashcards
What is the definition of a stroke?
Neurological defict:
- lasts more than 24hours
- Sudden
- From vascular origin
Can be either ischemic or hemorrhagic
TIA lasts less than 24hours and involves no infarction
Where does the carotid and the vertebro-basilar system supply?
Carotid system supplies the hemisphere and cortical deep white matter
Vertebrobasilar supplies the brain stem, cerebellum and occipital lobes
Define what a haemorrhagic stroke is, how its caused and its specialties
Its due to bleeding in the brain parenchyma
Caused by hypertension or aneurysm
Subspecialities: Primary intracerebral haem=70% Secondary haem=30% Also split furthur into 1. Subarachnoid haem 2.Atriovenous malformation
Define what an ischamic stroke is, how its caused and its sub specialities are
Its due to blockage of blood and oxygen flow to brain. Caused by thrombosis/Emboli
Subspecialities: Large artery athlerosclerosis eg: carotid = 35% cardioembolic eg: AF 25% Small artery occlusion eg: lacunar 25% Unknown/Cryptogenic 10-15% Rare less than 5%: -atrial dissection -venous sinus thrombosis
Give examples of modifiable and non-modifiable risk factors
Mod =
Hypertension, AF, Hypercholestrol/lipid
Unmod=
FH, Age, Race, Diabeties mellitus, Infective endocarditis, Sleep apnea
What is roughly the pathophysiology of ischaemic strokes?
Embolism/occlusion/athleroscleorsis all lead to decrease in cerebral blood flow
This causes 2 things:
- Decrease in O2 and glucose in infarct locations. This leads to increase anaerobic metabolism which can lead to necrosis and inflammation = weakness, slurred speech, visual field loss
- Increased glucose metabolism in penumbra which can lead to increase in infarct volume
What is the pathophysiology in both intracerebral and subarachnoid hemorrhage?
Intracerebral = bleeding in the brain parenchyma due to:
- trauma
- Chronic hyperT
- Amyloid deposit
- Arteriavenous deform
Subarachnoid=rupture arterial aneurysm due to:
- Trauma
- Ruptured arterial aneurysm
- Arteriovenous deform
What are the oxford classification subtypes of a stroke?
Total anterior circulation stroke
Partial anterior circulation stroke
Lacunar stroke
Posterior circulation stroke
What is the symptom criteria and related vessels for total anterior circulation stroke?
20%
Must have all 3:
- Homonymous hemianopia (vision loss)
- Weakness + sensory defict in arm, leg and face. (unilateral)
- Higher cerebral dysfunction
Occlusion of the internal carotid artery and the proximal middle cerebral artery
Location: Large cortical stroke
What is the symptom criteria and vessels affected for partial anterior circulation stroke?
35%
Must have 2/3 of:
- Weakness + sensory defict in face,arm and leg (unilateral)
- Homonymous hemianopia
- Higher cerebral dysfunction
Occlusion of branches of middle cerebral artery (Anterior or middle cerebral arteries)
Location: Cortical
What is the symptom criteria and vessels affected for lacunar stroke?
20%
Must have full loss of either:
Sensory - complete/incomplete weakness of 1 side involving 2/3 of body area
Motor -
Same distribution
Sensorimotor -
Combination of the above
Vessels= Small deep perforating arteries
Location=Subcortical
What is the symptom criteria and vessels affected for posterior circulation stroke?
25%
Brainstem, cerebellum or occipital lobes Variable, may include: -Coma -Eye movement -Bilateral motor/sensory deficit -Disordered breathing
Vessel= Post cerebral artery, vertebral artery, basilar artery and bracnhes
Which classification of stroke has the highest mortality rate?
TACS = 60%
List the general symptoms of a stroke
Acute onset Headache Neck stiff Arm/leg/facuak weakness Vomit Loss of speech, sensation, power and vision
FAST
After stroke, some people struggle to swallow (50%)
What is the circle of willis?
Ant, middle and post cerebral artery
Ant and post communicating artery
Internal carotid
Basilar and vertebral artery
