STROKE

DEFINITION

• Stroke is defined as abrupt onset of a neurologic deficit that is attributable to a focal vascular cause.

INTRODUCTION

• Stroke is second leading killer worldwide• Stroke is a neurological damage caused by reduction

of blood flow to the brain .The part of the brain damaged from loss of oxygen is called infarct

• It is also called brain attack

EPIDEMIOLOGY

• It is occurs in more than 70,00000 individuals per year and results in 1,50000 deaths.

• 75% of stroke occurs in elderly patients of age more than 65 years

ClassificationStroke

Hemorrhage (12%) intraparenchymal

subarachnoidalIshemic stroke(88%)

Atherosclerotic penetrating artery cardiogenic cryptogenic other unusualCerebrovascular diseases disease(20%) embolism(18%) stroke(30%) cause(5%)(15%) hypoperfusion Atrial fibrillation prothrombic atheriogenic emboli valve disease causes ventricular thrombi migraine vasospasm drug abuse dissections

ETIOLOGY

1) Non modifiable risk factors • Age• Gender• Race• Family history of stroke• Low birth weight

2) Modifiable• Hypertension• Atrial fibrillation• Diabetes • Cigratte smoking, alcohol• Sickle cell disease• Post menopausal hormone therapy

3) Potentially modifiable • Oral contraceptives• Migraine• Drug and alcohol abuse• Hemostatic and inflammatory factors• Sleep disorder

PathophysiologyIshemic stroke

Carotid atherosclerosis

Progressive accumulation of lipids and inflammatory cells in the intima of the affected

arteries

Hypertrophy of arterial smooth muscle cells

Plaque formation Stress

Plaque rupture ,collagen exposure ,platelet aggregation & clot formation

Clot remain in the vessel travel embolism

Local occlusion thrombus formation arterial occlusion decreasing cerebral blood flow ishemia

ishemic cell

reduction in nutrients

Depletion of high energy phospahtes (ATP) – maintains membrane integrity

Extracellular K+ Accumulates & Na and H2O intracellularly

Electrolyte imbalance cell swelling & lysis

leads to depolarization of the cell

influx of Ca ions

(+) lipases ,proteases, endonucleases ,release of free fatty acids from membrane phospholipids

accumulation of free fatty acids (arachidonic acids)

Formation of prostaglandins , leukotrienes, free radicals

Intracellular acidosis

occurs in 2-3 hrs

Cell death

Haemorrhage stroke

Presence of blood in the brain parenchyma ,neurotoxicity of the blood

Damage to the surrounding tissue & hemorrhage volumes >60ml

mortality at 30 days

increase in intracranial pressure leads to herniation and death

SIGNS AND SYMPTOMS

• Sudden numbness or weakness of face ,arm or leg especially affecting only one side of the body

• Confusion trouble in speaking or in understanding others

• Visual disturbances in one or both eyes means blurred or double vision

• Dizziness ,loss of balance and difficulty in walking and coordination

• Severe headache without apparent cause• Dysarthria.

DIAGNOSIS• EEG,ECG( Atrial fibrillation)• MRI• CT Scan-hyperintensity (white) –heamorrhage areas

normal or hypointense (dark)-infarction areas• Carotid doppler –stenosis in carotid arteries• Laboratory findings

1) Complete blood count

2) Coagulation test- protein c deficiency, anti -phospholipid antibody

3) Blood lipid test

4) Measure of cardiac enzymes like troponin, creatinine kinase

LDH isoenzymes

Management 1) Pharmacological • Acute ischemic stroke

plasminogen activator (alteplase) with in 3 hrs of onset . Dose -0.9 mg/kg I.V

aspirin within 48 hrs of onset . Dose -160-325 mg daily started within 48 hrs

Secondary prevention of ischemic stroke antiplatelet therapy

aspirin 50-325 mg daily clopidogrel 75 mg daily aspirin 25 mg +dipyridamole 200 mg twice daily

Anti hypertensive agent Statin therapy AF , Cardiac source of embolism –warfarin (INR-2.5)• Heamorrhage stroke

Nimodipine( Ca channel blockers) Carotid stenting

2) Non pharmacological treatment• Speech therapy• Psychological therapy• Stroke rehabilitation

physical therapy

occupational therapy

3) Surgical • carotid endarterectomy• EC/IC bypass surgery• Dipping• Detachable coil technique

Patient counselling1. Educate about symptoms that might indicate stroke and other

brain disease

2. Avoid smoking and use of alcohol

3. Regular exercise is advised

4. Reduce overweight

5. Decrease intake of high cholesterol and fat

6. Regular check up of BP, sugar, lipid should be done

7. Reduce salt intake