TIA and Stroke Flashcards
What is a Stroke and a TIA?
A stroke is clinical syndrome caused by disruption of blood supply to the brain. It is characterised by rapidly developing neurological disturbances, lasting for more than 24 hours or leading to death. A transient ischaemic attack (TIA) refers to a neurological event that resolves within 24 hours. A stroke results either from an ischaemic infarction of part of the brain or from intracerebral haemorrhage, however a TIA tends to be due to an ischaemic event, as symptoms are unlikely to regress within 24 hours of a haemorrhagic event
What are the causes of a stroke/TIA?
Ischaemic - Thromboembolism (Often from the carotids), Cardiac embolism (AF, Post MI, Heart/Valve Defect), In Situ Thrombosis, Hyper viscous blood (Polycythaemia, Sickle Cell Disease), Vasculitis (e.g. Giant Cell Arteritis/SLE), (Infective Endocarditis (Can release infective emboli)
Haemorrhagic - Hypertension, anticoagulation, aneurysm, trauma
What are the findings on history taking of a Stroke?
Symptoms: Will be dependent on the area of infarct
Anterior circulation stroke – Contralateral hemiplegia, Contralateral sensory loss, Homonymous hemianopia, Dysphasia.
Posterior circulation strokes - Homonymous hemianopia, Confusion, Dizziness, Nausea, Sensory or Motor Deficits, Individual Cranial nerve abnormalities
Lacunar stroke - Pure motor, Pure sensory or Mixed (motor and sensory), Ataxia
Risk Factors: Hypertension Smoking Diabetes Hyperlipidaemia Heart disease Family History Peripheral Vascular disease Previous Stroke/TIA OCP Alcohol Abnormal clotting
Specific questions to ask in a history taking:
Ask about contraindications to thrombolysis – Haemorrhagic Stroke, Recent Surgery/Trauma, Intracranial Neoplasm, Aneurism, Recent Internal bleeding, Recent LP, INR>1.7, Acute Pericarditis
Assess the time of onset – If Within 4.5 hours can use thrombolysis
Differentials: Head Trauma Hyper/Hypoglycaemia CNS tumour Intercranial Haemorrhage - CT scan to differentiate Hemiplegic migraine Drug use/overdose Seizure - Tongue biting, incontinence Electrolyte Abnormality
What are the findings on examination of a Stroke?
End of the bed: Assess GCS score Limbs: Hemiplegia Sensory loss Motor loss Face: Homonymous hemianopia Assess swallowing Assess cranial verves
What investigations will you order in suspected TIA/Stroke?
Bedside:
ECG - 24 hour to look for arrhythmias that may have caused an embolus
Eye examination with ophthalmoscope – Looking for Hypertensive Retinopathy
Urine Dipstick -Looking for End Artery Damage caused by chronic hypertension or underlying renal problems
Capillary Glucose - To exclude hypoglycaemia as a differential and to assess other cardiovascular risks
Bloods:
FBC – Looking for polycythaemia that may be a cause, look for any thrombocytopenia that may be a risk in thrombolysis.
U&E - Renal failure can contraindicate thrombolysis and to exclude electrolyte disturbances causing arrhythmias or neurological abnormality
ESR/ANCA – Ruling out any Vasculitic cause of clots (E.g. Giant Cell Arteritis)
Lipids – To assess other cardiovascular risks
Clotting - Thrombocytopaenia or contraindication to thrombolysis
Troponin - Exclude MI as cause of stroke
Test for Sickle Cell disease
Imaging:
CXR - Show signs of cardiomegaly or heart failure indicating chronic hypertension
CT/MRI Head – Diagnostic test within 1 hour
24-hour post CT to exclude bleeds
Echo – Looking for any cause of a clot
Special Tests:
Carotid Doppler with angiography – To look for any atherosclerotic narrowing of the carotids that may have been the cause of a clot
What is the emergency treatment of a stroke?
Resuscitation
A-E approach
Get IV Access/Give O2 to maintain sats of 94+ /Attach 12 lead ECG
Assessment with AMPLE history and brief examination
Get help - Cardio-thoracic surgeon
Refer to Stroke Unit
Frequent Observations - Constant or 15 minutely
Protect airways
CT/MRI within 1 hour - To see the type of stroke, assessing for use of thrombolysis
Medical:
Haemorrhagic Stroke - Refer to ITU and call neurosurgeon and keep BP low
Ischaemic Stroke - Aspirin 300mg
< 4.5 hours give thrombolysis (Alteplase)
>4.5 Hours or Contraindicated - refer to stroke ward, continue aspirin and give VTE prophylaxis (to prevent DVT)
What is the chronic treatment of a Stroke/TIA?
Lifestyle: Swallowing screen – If impaired NG Tube (Short Term) or PEG (Long Term) Encourage mobility and Physiotherapy Stop Smoking Optimise BMI Patient can’t drive for 1 month
Medical:
Reduce Cardiovascular Risk - BP management, Lipid management, Diabetes Management, Dual Anti-platelet therapy - Aspirin 300mg 2 weeks, then swap for Clopidogrel 75mg lifelong
Patient may need anticoagulation for underlying cause e.g. in AF
Surgical:
If Stenosis of carotids on doppler > 70% - Carotid Endarterectomy (Removal of the atheromatous build up inside the carotid artery) or Endovascular repair with stents.
What scoring system is used in patients post TIA
ABCD score used to assess risk of stroke post TIA
Age > 60
BP - Hypertension
Clinical features of stroke - unilateral weakness, speech disturbances
Duration of symptoms - >1 hour
Diabetes
High scores (>3) must be assessed by TIA specialist within 24 hours
