CEREBROVASCULAR ACCIDENTS Prof Magdy Dahab Al Aqiq General

CEREBROVASCULAR ACCIDENTS Prof. Magdy Dahab Al Aqiq General Hospital March 30 th, 2014

OBJECTIVES Ø Define “stroke” Ø Discuss incidence & risk factors Ø Review Cerebral flow and factors that affect it Ø Discuss pathophysiology of CVA Ø Correlate clinical manifestations of stroke with the pathophysiology. Stroke M Dahab 2

DEFINITION Ø Ischemia is inadequate blood flow Ø Brain attack (Stroke) occurs when there is ischemia to a part of the brain that results in death of brain cells Stroke M Dahab 3

INCIDENCE v 3 rd Cause of death in the world • Statistics Ø 2/3 in people >65 Ø = in men and women Ø Higher incidence and death rates among African. Americans, Hispanics, Native-American, Asian Americans Stroke M Dahab 4

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What is a Stroke ? Lack of blood flow to the brain caused by a clot or rupture of a blood vessel Sudden brain damage v. Ischemic • Most common • Caused by a clot Embolic Thrombotic • Hemorrhagic –Bleeding around brain –Bleeding into brain Stroke M Dahab 6

RISK FACTORS Non Modifiable Ø Age Ø Gender Ø Race Ø Heredity Stroke M Dahab 7

RISK FACTORS Modifiable v Asymptomatic carotid stenosis v Obesity v Diabetes mellitus v HTN v Heart disease, atrial fibrillation v Smoking v Oral contraceptives v Heavy alcohol consumption v Physical inactivity v Hypercoagulability v Sickle cell disease v Hyperlipidemia Stroke M Dahab 8

REVIEW OF CEREBRAL CIRCULATION Stroke M Dahab 9

“BRAIN ATTACK” MEANS: Blood flow to the brain is totally interrupted Stroke M Dahab 10

ETIOLOGY v. Atherosclerosis – Disease of the arteries; hardening and thickening of the arterial wall because of soft deposits of intra-arterial fat and fibrin that harden over time. Stroke M Dahab 11

VESSELS OF THE BRAIN Stroke M Dahab 12

CIRCLE OF WILLIS Stroke M Dahab 13

COMMON SITES FOR THE DEVELOPMENT OF ATHEROSCLEROSIS Stroke M Dahab 14

TRANSIENT ISCHEMIC ATTACK (TIA) Ø Transient ischemic attack (TIA) is a temporary focal loss of neurologic function caused by ischemia Ø Most TIAs resolve within 3 hours Ø TIAs are a warning sign of progressive cerebrovascular disease Stroke M Dahab 15

ISCHEMIC VS. HEMORRHAGIC Stroke M Dahab 16

ISCHEMIC STROKE Ø Ischemic strokes result from inadequate blood flow to the brain from partial or complete occlusion of an artery Ø 85% of all strokes are ischemic strokes Stroke M Dahab 17

ISCHEMIC STROKE v Thrombotic or Embolic Ø Most patients with ischemic stroke do not have a decreased level of consciousness in the first 24 hours Ø May progress in the first 72 hours Stroke M Dahab 18

THROMBOTIC STROKE Ø Thrombosis occurs in relation to injury to a blood vessel wall and formation of a blood clot Ø Result of thrombosis or narrowing of the blood vessel Ø Most common cause of stroke Stroke M Dahab 19

THROMBOTIC STROKE Ø Occlusion of large cerebral vessel Ø Older population Ø Sleeping/resting Ø Rapid event, but slow progression (usually reach max deficit in 3 days) Stroke M Dahab 20

EMBOLIC STROKE Ø Occur when an embolus lodges in and occludes a cerebral artery Ø Results in infarction and edema of the area supplied by the involved vessel Ø Second most common cause of stroke Stroke M Dahab 21

EMBOLIC STROKE Ø Embolus becomes lodged in vessel and causes occlusion Ø Bifurcations are most common site Ø Sudden onset with immediate deficits Ø Embolysis Ø Hemorrhagic Transformation Stroke M Dahab 22

HEMORRHAGIC STROKE Ø Account for approximately 15% of all strokes Ø Result from bleeding into the brain tissue itself or into the subarachnoid space or ventricles Stroke M Dahab 23

HEMORRHAGIC STROKE v Intracerebral hemorrhage Ø Bleeding within the brain caused by a rupture of a vessel Ø Hypertension is the most important cause Ø Hemorrhage commonly occurs during periods of activity Stroke M Dahab 24

HEMORRHAGIC STROKE v Subarachnoid hemorrhage Ø Occurs when there is intracranial bleeding into cerebrospinal fluid-filled space between the arachnoid and pia mater Ø Commonly caused by rupture of a cerebral aneurysm Stroke M Dahab 25

HEMORRHAGIC STROKE Ø Rupture of vessel Ø Sudden Ø Active Ø Fatal Ø HTN Ø Trauma Ø Varied manifestations Stroke M Dahab 26

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CLINICAL MANIFESTATIONS v. Affects many body functions Ø Ø Ø Ø Stroke Motor activity Elimination Intellectual function Spatial-perceptual alterations Personality Affect Sensation Communication M Dahab 28

Stroke Symptoms Sudden numbness or weakness of face, arm or leg, especially on one side of the body Sudden confusion, trouble speaking or understanding Sudden trouble walking, dizziness, loss of balance or coordination Sudden trouble seeing in one or both eyes Sudden severe headache with no known cause Stroke M Dahab 29

THE PERCEPTIONS OF STROKE MYTH REALITY Ø Stroke is not preventable Ø Many strokes are preventable Ø Stroke cannot be treated Ø Stroke can be treated Ø Stroke only strikes the Ø Anyone can have a stroke elderly Ø Stroke happens in the heart Ø Stroke recovery ends after 6 Ø Stroke is a “Brain Attack” Ø Stroke recovery can months Stroke last a lifetime M Dahab 30

DIAGNOSTIC STUDIES Ø When symptoms of a stroke occur, diagnostic studies are done to Ø Confirm that it is a stroke Ø Identify the likely cause of the stroke Ø CT is the primary diagnostic test used after a stroke Stroke M Dahab 31

DIAGNOSTIC STUDIES v Additional studies Ø Complete blood count Ø Platelets, prothrombin time, activated partial thromboplastin time Ø Electrolytes, blood glucose Ø Renal and hepatic studies Ø Lipid profile Stroke M Dahab 32

COLLABORATIVE CARE PREVENTION v Goals of stroke prevention include Ø Health management for the well individual Ø Education and management of modifiable risk factors to prevent a stroke Stroke M Dahab 33

COLLABORATIVE CARE PREVENTION Ø Antiplatelet drugs are usually the chosen treatment to prevent further stroke in patients who have had a TIA Ø Aspirin is the most frequently used antiplatelet drug Stroke M Dahab 34

COLLABORATIVE CARE PREVENTION v Surgical interventions for the patient with TIAs from carotid disease include Ø Ø Stroke Carotid endarterectomy Transluminal angioplasty Stenting Extracranial-intracranial bypass M Dahab 35

COLLABORATIVE CARE ACUTE CARE v Assessment findings Ø Ø Ø Ø Stroke Altered level of consciousness Weakness, numbness, or paralysis Speech or visual disturbances Severe headache ↑ or ↓ heart rate Respiratory distress Unequal pupils M Dahab 36

COLLABORATIVE CARE ACUTE CARE v Interventions – Initial Ø Ø Ø Stroke Remove clothing Obtain CT scan immediately Perform baseline laboratory tests Position head midline Elevate head of bed 30 degrees if no symptoms of shock or injury M Dahab 37

COLLABORATIVE CARE ACUTE CARE v. Recombinant tissue plasminogen activator (t. PA) is used to • Reestablish blood flow through a blocked artery to prevent cell death in patients with acute onset of ischemic stroke symptoms Stroke M Dahab 38

COLLABORATIVE CARE ACUTE CARE Ø Thrombolytic therapy given within 3 hours of the onset of symptoms Ø ↓ disability Ø But at the expense of ↑ in deaths within the first 7 to 10 days and ↑ in intracranial hemorrhage Stroke M Dahab 39

COLLABORATIVE CARE ACUTE CARE v Surgical interventions for stroke include immediate evacuation of Ø Aneurysm-induced hematomas Ø Cerebellar hematomas (>3 cm) Stroke M Dahab 40

COLLABORATIVE CARE REHABILITATION CARE v. After the stroke has stabilized for 12 -24 hours, collaborative care shifts from preserving life to lessening disability and attaining optimal functioning v. Patient may be transferred to a rehabilitation unit Stroke M Dahab 41

Now go to www. magdydahab. com to find more related lectures about most subjects of NEUROLOGY Thank you Stroke M Dahab 42