Cerebrovascular event (stroke) Flashcards
(26 cards)
What is a stroke?
Sudden onset focal neurological deficit of vascular aetiology. Symptoms typically last >24 hours (or with evidence of infarction on imaging).
Types of stroke?
Stroke can be categorised into 2 types:
Ischaemic stroke (85% of cases)
Haemorrhagic stroke (15% of cases)
- Intracerebral haemorrhages (75%)
- Subarachnoid haemorrhages (25%)
Strong risk factors for ischaemic stroke?
Age
Male sex
Family history of ischaemic stroke
Haemophilia
Weaker risk factors for ischaemic stroke?
Hypercholesterolaemia
Obesity
Poor diet
Migraine
Strong risk factors for haemorrhagic stroke?
Older age
Male sex
Family history of haemorrhagic stroke
Haemophilia
Weaker risk factors for haemorrhagic stroke?
NSAID’s
Thrombocytopenia
Heavy alcohol use
How does an ischaemic stroke occur?
Occurs when blood supply in a cerebral vascular territory is reduced secondary to stenosis or complete occlusion of a cerebral artery.
How does haemorrhagic stroke occur?
Bleeding occurs inside or around brain tissue due to the rupture of a blood vessel.
What is a common cause of haemorrhagic stroke?
Hypertension
Additional causes of haemorrhagic stroke?
Weakened blood vessel wall e.g. aneurysm, vasculitis
Stroke symptoms are typically symmetrical. True/false?
False
Typically asymmetrical
Typical symptoms of stroke?
- Sudden weakness of limbs
- Sudden facial weakness
- Sudden onset speech disturbance (dysphagia) - dysarthria (slurred speech), aphasia (expressive or receptive)
- Sudden onset visual or sensory loss
Anterior or middle cerebral artery stroke symptoms?
Numbness, sudden muscle weakness
Broca’s area (left frontal lobe) stroke symptoms?
expressive aphasia (difficulty producing speech)
Wenicke’s area (left temporal lobe) stroke symptoms?
receptive aphasia (difficulty understanding speech - patient typically speaks in ‘word salad’)
Posterior cerebral artery stroke symptoms?
affects vision
What is a major cause of stroke?
AF (atrial fibrillation)
Features of total anterior circulation syndrome?
- Involves the anterior AND middle cerebral arteries on the affected side
- Defined by:
- Contralateral hemiplegia or hemiparesis, AND
- Contralateral homonymous hemianopia, AND
- Higher cerebral dysfunction (e.g. aphasia, neglect)
Features of partial anterior circulation syndrome?
- Involves the anterior OR middle cerebral artery on the affected side
- Defined by:
- 2 out of the 3 features present in a TACS OR
- Higher cerebral dysfunction alone e.g. dysphagia
Features of posterior circulation stroke?
- Involves the vertebrobasilar arteries and associated branches (supplying the cerebellum, brainstem, and occipital lobe)
- Defined by:
- Cerebellar dysfunction, OR
- Conjugate eye movement disorder, OR
- Bilateral motor/sensory deficit, OR
- Ipsilateral cranial nerve palsy with contralateral motor/sensory deficit, OR
- Cortical blindness/isolated hemianopia
Features of lacunar stroke?
- Small infarcts around the deeper parts of the brain (basal ganglia, internal capsule, thalamus and pons) caused by occlusion of a single deep single penetrating artery
- Defined as: a pure motor stroke, pure sensory stroke, sensorimotor stroke, or ataxic hemiparesis
- There should be NO: visual field defect, higher cerebral dysfunction, or brainstem dysfunction
- Best prognosis of all the strokes with 60% of patients alive and independent at 1 year
Basilar artery occlusion features?
More likely to present with locked in syndrome (quadriparesis with preserved consciousness and ocular movements), loss of consciousness, or sudden death
In this, the person is completely paralysed however remains conscious and eye movement is preserved.
Wallenberg’s syndrome (lateral medullary syndrome) features?
ipsilateral Horner’s syndrome,
ipsilateral loss of pain and temperature sensation on the face,
contralateral loss of pain and temperature sensation over the contralateral body
Acute management of stroke?
- DR ABCDE approach
- Airway protection (in patients presenting with depressed consciousness) and aspiration precautions (in patients presenting with swallowing impairment) are very important