Stroke Flashcards
Definition of stroke
Rapid onset neurological deficit of vascular origin lasting >24h
Pathogenesis of stroke
80% ischaemic: atheroma or embolism (cardiac or atherothromboembolism)
20% hamorrhagic
Classification system for strokes
Bamford classification AKA Oxford Stroke classification:
TACS (total anterior circulation stroke) - carotid/MCA/ACA
PACS (partial anterior circulation stroke) - carotid/MCA/ACA
POCS (posterior circulation syndrome) - vertebrobasilar
LACS (lacunar syndrome) - infarct around basal ganglia/internal capsule/thalamus/pons
Features of TACS stroke
Carotid/MCA/ACA territory.
- Hemiparesis and/or hemisensory deficit.
- Homonymous hemianopia.
- Higher cortical dysfunction: dominant side - aphasia, non-dominant - neglect, apraxia.
Features of PACS stroke
2 out of 3 of TACS features, usually: homonymous hemianopia + higher cortical dysfunction.
Features of POCS stroke
Vertebrobasilar territory. Any of: 1. Cerebellar syndrome 2. Brainstem syndrome 3. Homonymous hemianopia.
Features of LACS stroke
Pure motor: posterior limb of internal capsule
Pure sensory: posterior thalamus (VPL)
Mixed sensorimotor: internal capsule
Dysarthria/clumsy hand
Ataxic hemiparesis: posterior limb of internal capsule
Differential for acute stroke
Head injury High or low glucose SOL Infection Drugs e.g. opiate OD
Acute management of stroke
- Resuscitate:
Airway - consider NGT. NBM until assessed by SALT. Don’t over hydrate - risk of cerebral oedema. BM to exclude hypoglycaemia. - Monitor: glucose 4-11mM (sliding scale if DM). BP: Rx of HTN can decrease cerebral perfusion. Neuro obs.
- Bloods
- Imaging
- Medical:
Aspirin 300mg PO/PR once haemorrhage stroke excluded by CT, then continue 75mg OD indefinitely, + clopidogrel 75mg OD, ± PPI.
Thrombolysis with alteplase if within 4.5h and haemorrhage excluded. Pause antiplatelets. Re-image 24h afterwards to check for haemorrhage.
Blood tests in acute stroke
FBC: infection. sepsis may cause stroke.
U+E: electrolyte disturbance may mimic stroke.
Glucose: exclude hypoglycaemia.
Clotting: high or low INR may indicate cause.
Imaging in acute stroke
Urgent CT/MRI
Diffusion-weighted MRI is most sensitive for acute infarct
CT will exclude primary haemorrhage
Surgical tx in acute stroke
Neurosurgical opinion if intracranial haemorrhage
May coil bleeding aneurysms
Decompressive hemicraniotomy for some forms of MCA infarction
Main functions of a stroke unit
Specialist nursing and physiology
Early mobilisation
DVT prophylaxis
Post-acute management of stroke
Secondary prevention
Rehabilitation
Non-acute stroke work-up investigations
ECG ± 24h tape: arrhythmia, old ischaemia.
Bloods: FBC (high or low Hb), U+E (association with renovascular disease), glucose (exclude DM), lipids (CV risk), clotting and thrombophilia screen, vasculitis (ESR, ANA),
Imaging: CXR (cardiomegaly, aspiration), carotid doppler, echo (mural thrombus, RWMA, ASD/VSD (paradoxical emboli)).
Components of a thrombophilia screen
FBC, clotting, fibrinogen concentration. APC resistance AKA factor V Leiden. Lupus anticoagulant. Anti-cardiolipin antibodies. Assays for protein C and S and AT3 activity. PCR for prothrombin gene mutation.
Secondary prevention of stroke
AABCDEE Antiaggregants and anticoagulants. Blood pressure drugs. Cigarette smoking cessation. Diet Exercise Endarterectomy of carotids if stable and stenosis >50%.
Rehabilitation after stroke
MENDS
MDT
Eating: screen swallowing and screen malnutrition (MUST tool). NG/PEG and nutritional supplements as needed.
Neurorehab: physiology and speech therapy. Botulinum for spasticity.
DVT prophylaxis.
Sores must be avoided.
Tool for assessing malnutrition
MUST tool (malnutrition universal screening tool)
Prognosis for stroke @ 1 year
10% recurrence
PACS: 20% mortality, 1/3 survivors independent.
TACS much worse: 60% mortality, 5% independent.
