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 📚 STROKE – Detailed Version

🔍 1. What is Stroke?

  • Definition:
    A stroke (also called cerebrovascular accident – CVA) is a sudden, focal neurological deficit due to disturbance of blood supply to the brain, causing ischemia or hemorrhage.

🧠 2. Types of Stroke

🔸 A. Ischemic Stroke (≈85% of cases)

  • Cause: Blockage of a cerebral artery leading to reduced blood flow.

  • Types:

    1. Thrombotic stroke – clot forms at the site of atherosclerotic plaque.

    2. Embolic stroke – clot travels from elsewhere (e.g., from heart in atrial fibrillation).

    3. Lacunar infarct – small vessel occlusion (deep brain).

🔸 B. Hemorrhagic Stroke (≈15% of cases)

  • Cause: Rupture of a blood vessel causing bleeding into/around the brain.

  • Types:

    1. Intracerebral hemorrhage – bleeding into brain tissue.

    2. Subarachnoid hemorrhage – bleeding into subarachnoid space (often due to ruptured aneurysm).

🧬 3. Pathophysiology

  • Brain tissue relies on constant blood flow for oxygen and glucose.

  • Ischemia → energy failure → Na⁺/K⁺ pump failure → cell swelling, glutamate release → excitotoxicity → calcium influx → cell death (infarction).

  • Hemorrhage → mass effect, increased intracranial pressure (ICP), and direct neuronal damage.

🌱 4. Risk Factors

🔸 Non-modifiable:

  • Age, male gender, family history, race (African descent at higher risk).

🔸 Modifiable:

  • Hypertension (most important), diabetes mellitus, smoking, hyperlipidemia, atrial fibrillation, carotid artery disease, obesity, sedentary lifestyle, alcohol abuse.

📝 5. Clinical Features (Depends on area affected)

🔹 Common signs:

  • Sudden weakness/numbness of face, arm, or leg (usually one-sided).

  • Aphasia (language impairment, if dominant hemisphere).

  • Dysarthria (slurred speech).

  • Hemianopia (visual field defect).

  • Ataxia, vertigo (brainstem or cerebellar stroke).

  • Sudden severe headache (suggestive of hemorrhage).

🔹 FAST mnemonic (for public awareness):

  • Face drooping.

  • Arm weakness.

  • Speech difficulty.

  • Time to call emergency services.

🏥 6. Diagnosis

🔸 A. Clinical assessment

  • Neurological exam: NIH Stroke Scale (NIHSS) quantifies stroke severity.

  • History: Onset time (critical for treatment decisions).

🔸 B. Imaging

  • Non-contrast CT scan:

    • Rule out hemorrhage.

    • May be normal in early ischemic stroke.

  • MRI with DWI: sensitive for detecting early infarcts.

  • CT angiography (CTA) / MR angiography (MRA): assess blood vessels for occlusion or aneurysm.

🔸 C. Laboratory tests

  • Blood glucose (rule out hypoglycemia).

  • Coagulation profile.

  • Lipid panel, cardiac enzymes, ECG.

💊 7. Management of Stroke

🔹 A. Acute Management (First hours)

✅ Ischemic stroke:

  • IV thrombolysis (tPA – alteplase) within 4.5 hours of onset (if no contraindications).

  • Mechanical thrombectomy (large vessel occlusion) within 6–24 hours.

  • Aspirin (if tPA not given) within 24–48 hours.

✅ Hemorrhagic stroke:

  • Blood pressure control.

  • Reverse anticoagulation (if on blood thinners).

  • Surgical intervention (e.g., hematoma evacuation, aneurysm clipping/coiling).

🔹 B. Supportive Care

  • Maintain airway, breathing, and circulation (ABCs).

  • Prevent aspiration pneumonia.

  • Monitor and control blood glucose and temperature.

  • Prevent DVT with compression stockings.

🔹 C. Secondary Prevention

  • Antiplatelet therapy (aspirin, clopidogrel) for ischemic stroke.

  • Anticoagulation if cardioembolic source (e.g., atrial fibrillation).

  • Statins for lipid control.

  • Blood pressure control.

  • Lifestyle changes: smoking cessation, diet, exercise.

🏃‍♂️ 8. Rehabilitation

  • Physiotherapy: improves motor recovery, balance, strength.

  • Speech therapy: for aphasia and dysphagia.

  • Occupational therapy: for daily activities and adaptive strategies.

  • Psychological support: depression is common after stroke.

🚨 9. Complications

  • Hemorrhagic transformation (in ischemic stroke).

  • Seizures.

  • Infections (e.g., pneumonia, UTIs).

  • Deep vein thrombosis (DVT).

  • Chronic disability: motor deficits, cognitive impairment, depression.

🎓 10. Summary Table

Feature Ischemic Stroke Hemorrhagic Stroke
Cause Vessel occlusion (thrombus/embolus) Vessel rupture (bleeding)
Commonality ~85% ~15%
Onset Sudden, focal Sudden, severe headache common
Imaging CT scan, MRI CT scan (hyperdense area)
Treatment window tPA within 4.5 hours BP control, surgery if needed
Risk factors HTN, diabetes, AF, smoking HTN, aneurysm, anticoagulants


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