Stroke Flashcards
Draw the Circle of Willis and annotate it
Outline the blood supply of the brain
Cerebrovascular accidents are either:
- Ischaemia or infarction of brain tissue secondary to inadequate blood supply
- Intracranial haemorrhage
What are the causes of ischaemic stroke?
Embolism: an embolus originating somewhere else in the body (e.g. the heart) causes obstruction of a cerebral vessel, resulting in hypoperfusion to the area of the brain the vessel supplies.
Thrombosis: a blood clot forms locally within a cerebral vessel (e.g. due to atherosclerotic plaque rupture).
Systemic hypoperfusion: blood supply to the entire brain is reduced secondary to systemic hypotension (e.g. cardiac arrest).
Cerebral venous sinus thrombosis: blood clots form in the veins that drain the brain, resulting in venous congestion and tissue hypoxia
In which ways may cerebral blood flow be disrupted?
- Thrombus formation or embolus, for example in patients with atrial fibrillation
- Atherosclerosis
- Shock
- Vasculitis
What is a TIA?
transient neurological dysfunction secondary to ischaemia without infarction
What is a crescendo TIA?
A crescendo TIA is where there are two or more TIAs within a week. This carries a high risk of developing in to a stroke.
How does stroke normally present?
In neurology, suspect a vascular cause where there is a sudden onset of neurological symptoms.
Stoke symptoms are typically asymmetrical:
- Sudden weakness of limbs
- Sudden facial weakness
- Sudden onset dysphasia (speech disturbance)
- Sudden onset visual or sensory loss
Outline the risk factors for stroke
- Cardiovascular disease such as angina, myocardial infarction and peripheral vascular disease
- Previous stroke or TIA
- Atrial fibrillation
- Carotid artery disease
- Hypertension
- Diabetes
- Smoking
- Vasculitis
- Thrombophilia
- Combined contraceptive pill
What is the ROSIER tool?
Recognition of stroke in emerggency room (ROSIER) is a clinical scoring tool based on clinical features and duration. Stroke is likely if the patient scores anything above 0.
Outline some important differential diagnoses of a stroke
• Migraine
• Epilepsy
• Structural brain lesions (SDH, Tumour,
abscess)
• Metabolic/toxic disorders (hypoglycemia)
• Vestibular disorders
• Functional weakness
• Demyelination
• Mononeuropathy
What are some important features to delineate within a stroke history?
- Onset
- Course
- Focal vs general symptoms
- “Negative” symptoms (loss of function)
+ risk factors
What are 3 important considerations when thinking of thrombolysis?
- Clear time of onset (less than 4 ½ h)
- No contra-indications
- Infarct v haemorrhage
How quickly should patients get a CT scan of their brain?
Within 1 hour
What indications are there for an urgent scan?
Urgent scan if:
• Thrombolysis or early anticoagulation being considered
• On anticoagulant treatment
• A known bleeding tendency
• Depressed level of consciousness (GCS < 13)
• Unexplained progressive or fluctuating symptoms
• Papilloedema, neck stiffness or fever
• Severe headache at onset
How is stroke managed?
- Admit patients to a specialist stroke centre
- Exclude hypoglycaemia
- Immediate CT brain to exclude primary intracerebral haemorrhage
- Aspirin 300mg stat (after the CT) and continued for 2 weeks
- Thrombolysis with alteplase
- Thrombectomy