Stroke

Exam Cram

• Stroke is caused by acute hypoperfusion to brain tissue resulting in infarction

• Strokes: 80% ischaemic, 20% haemorrhagic

• Presentation: sudden onset focal neurology

• Diagnosis: clinical, CT-H or MRI-H

• Ischaemic Stroke Management:

  1. Treat clot: antiplatelets, thrombectomy or thrombolysis

  2. Investigate for underlying cause

Outline

Background

Diagnosis

Diagnostic criteria: 

History:

Examination:

Ix

Differentials

Background

Classifying Strokes

1. Acute aetiology

   1. Ischaemic

   2. Hemorrhagic

2. Underlying case

   1. Primary

   2. Secondary

3. Blood supply

   1. Anterior (carotids)

   2. Posterior (vertebral)

4. Location of brain tissue anatomy

   1. Cerebrum (frontal, parietal, temporal, and occipital lobes)

   2. Cerebellar

   3. Brainstem (pons, medulla, midbrain)

5. Symptoms

1. Acute Aetiology

• Ischaemic

  • Thrombus

  • Dissection

Dissection

• Definition: inner lining of the artery tears off into the lumen of the blood vessel, reducing the blood flow through the vessel

• Classified as a type of ischaemic event, usually managed with antiplatelets

• Haemorrhagic

2. Underlying Cause

3. Lesion By Blood supply

Anterior

Carotid dissection

Tall thin, exercise induced neck pain, o/e horner's

Middle cerebral artery

• Broca- Brodmann 44/45's area: frontal dominant lobe- inferior gyrus: expressive dysphagia

• Wernicke's- Brodmann 220 dominant temporal lobe, superior: receptive dysphagia

Anterior circulation lesion

• Left hemiparesis + fixed gaze palsy to the right (contralateral gaze fixation)

Posterior

Posterior circulation lesion

• Left hemiparesis + fixed gaze palsy to the left (ipsilateral gaze fixation)

Lateral medullary syndrome: 

• Posterior inferior cerebellar or vertebral artery

• Spinothalamic lesion: ipsilateral facial, contralateral lower limb

• 80% fully recover within 6 months

Posterior communication artery aneurysm

• 50% intracerebral aneurysms

• Persistent headaches + CN III palsy

Anton Syndrome

• Bilateral occipital lobe lesions

• Presents with bilateral blindness and confabulation

• Areas vulnerable to prolonged hypotension

Posterior cerebral artery (PCA)

• Weber Syndrome: ipsilateral CN 3 palsy & contralateral hemiplegia

Vertebral artery dissection

• Associations: whiplash injury

• Presentation: posterior head and neck pain, nystagus & unilateral tongue weakness

4. Lesion by Location

Cavernous sinus

• Lesion involving CN III, IV, VI and trigeminal V1

Frontal Lobe

• • Personality changes

  • Broca- Brodmann 44/45's area: frontal dominant lobe- inferior gyrus: expressive dysphagia

Temporal Lobe

• • Homonymous hemianopia superior- PITS

  • Wernicke's- Brodmann 220 dominant temporal lobe, superior: receptive dysphagia

Parietal Lobe

• • Homonymous hemianopia inferior- PITS

  • Dominant: difficulty reading, acalculia, dyslexia, agnosia, acalculia, agraphia

  • Receptive dysphasia

Occipital Lobe

5. By Symptom

Homonymous hemianopia

• PITS: parietal inferior, temporal superior

Ischaemic Management

Hyper-Acute 

• Thrombectomy: within 24hrs OR

• Thrombolysis: within 4.5hrs OR

• Dual antiplatelet: 300mg aspirin + 300mg clopidogrel

Acute

1. TED Stockings without VTE prophylaxis

2. Nil by mouth with IV fluids

3. Admit Stroke Ward for MDT

1. • Stroke consultant review

   • Physio

   • Occupational therapist

   • Speech and language (swallow assessment)

   • DC planning

4. Investigate for secondary causes

   • Blood glucose vs HbA1c

   • ECHO ? PFO/ ASD

   • Carotid USS ?carotid stenosis

   • Consider CT-Angio, MRI-H

   • Consider thrombophilia screen

5. Consider Secondary prophylaxis

6. Tolerate BP > 210/110

Discharge Planning

1. Haematological (after two weeks)

   • Convert antiplatelets to long term clopidogrel 75mg

   • Stop Ted stockings and start VTE prophylaxis

   • If AF, convert start anticoagulation

2. Weekly MDT discharge planning, 

3. FU Investigations

Primary Prevention

Definition: preventing stroke in those who haven't had a stroke

• Lifestyle: low salt, regular exercise, avoid recreational stimulant drugs (cocaine), smoking and alcohol excess

• BP < 140/90 using antihypertensives

• Statin if cardiovascular 10 year risk > 10%

Secondary Prevention

Definition: preventing another stroke in patient who have already had at least one stroke

• Long term clopidogrel 75mg OD (until risks > benefit)

• Atorvastatin 80mg nocte

• BP < 140/90; indapamide may provide further benefit

• Secondary causes

  • Atrial fibrillation = direct oral anticoagulant (e.g. Apixaban)

  • Patent foramen ovale: consider closure

  • Carotid artery stenosis: consider carotid endarterectomy

  • Thrombophilia

Med Reg Notes

Thrombolysis Agents

Thrombolysis: alteplase- human tissue plasminogen activator. 

Existing anticoagulants

If on warfarin (INR 3 )for a mechanical valve and presents with an ischaemic stroke:

• No requirement for thrombolysis as already anticoagulated

• Continue warfarin as no evidence of current hemorrhagic transformation, highest risk straight after stroke so if present late e.g. > 48hrs

• If immediate presentation, can convert to LMWH if concerned about haermorrhagic transformation risk

Causes of stroke

• Cardioembolic: atrial fibrillation, PFO

• Large vessel disease: carotid stenosis

• Small vessel disease: vasculitis

• Thrombophilia

Indications for a Hemi-craniotomy

• Under 60yrs

• NIHSS > 15

• GCS < 15

• CT MCA infarct of > 50% or infarct volume > 145cm3

Haemorrhagic Stroke

Types

• Subarachnoid Haemorrhage 

• Intracranial Haemorrhage (ICH)

Acute Management

• Aim BP < 140/90 

• Consider Neurosurgical input

• IV labetolol

  • Nicardipine

Long Term Prevention (secondary prevention)

• Statin

• Antihypertensives

References & Resources

1. https://bnf.nice.org.uk/treatment-summaries/stroke/ 

2. https://www.strokeguideline.org/contents/?_gl=1*1w5hd3l*_up*MQ..*_ga*MTY3NTI1MjQ2LjE3MzkwMzM3NzU.*_ga_EE3BZMVLRT*MTczOTAzMzc3NC4xLjAuMTczOTAzMzc3NC4wLjAuMA

Page written in 2024.