Cerebrovascular Accident (CVA) mashehabat@just.edu.jo

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

Incidence 3rd Cause of death in US and Canada 2/3 in people >65 Statistics 2/3 in people >65 = in men and women Higher incidence and death rates among African-Americans, Hispanics, Native-American, Asian Americans

Risk Factors Non Modifiable Age Gender Race Heredity

Risk Factors Modifiable Obesity HTN Smoking Heavy alcohol consumption Hypercoagulability Hyperlipidemia Asymptomatic carotid stenosis Diabetes mellitus Heart disease, atrial fibrillation Oral contraceptives Physical inactivity Sickle cell disease

Review of Cerebral Circulation

Blood supply by arteries Blood is supplied to the brain by two major pairs of arteries Internal carotid arteries Vertebral arteries

Blood supply by arteries Carotid arteries branch to supply most of the Frontal, parietal, and temporal lobes Basal ganglia Part of the diencephalon Thalamus Hypothalamus

Blood supply by arteries Vertebral arteries join to form the basilar artery, which supply the Middle and lower temporal lobes Occipital lobes Cerebellum Brainstem Part of the diencephalon

Blood flow to the brain is totally interrupted “Brain Attack” means: Blood flow to the brain is totally interrupted

Etiology Atherosclerosis – Disease of the arteries; hardening and thickening of the arterial wall because of soft deposits of intraarterial fat and fibrin that harden over time.

Common sites for the development of Atherosclerosis

Transient Ischemic Attack (TIA) Transient ischemic attack (TIA) is a temporary focal loss of neurologic function caused by ischemia Most TIAs resolve within 3 hours TIAs are a warning sign of progressive cerebrovascular disease

Types of Stroke Strokes are classified based on the underlying pathophysiologic findings Ischemic Hemorrhagic

Ischemic vs. Hemorrhagic

Ischemic Stroke Ischemic strokes result from inadequate blood flow to the brain from partial or complete occlusion of an artery 85% of all strokes are ischemic strokes

Ischemic Stroke Thrombotic or Embolic Most patients with ischemic stroke do not have a decreased level of consciousness in the first 24 hours May progress in the first 72 hours

Thrombotic stroke Thrombosis occurs in relation to injury to a blood vessel wall and formation of a blood clot Result of thrombosis or narrowing of the blood vessel Most common cause of stroke

Embolic stroke Occur when an embolus lodges in and occludes a cerebral artery Results in infarction and edema of the area supplied by the involved vessel Second most common cause of stroke

Embolic stroke Majority of emboli originate in the inside layer of the heart, with plaque breaking off from the endocardium and entering the circulation Patient with an embolic stroke commonly has a rapid occurrence of severe clinical symptoms

Hemorrhagic Stroke Account for approximately 15% of all strokes Result from bleeding into the brain tissue itself or into the subarachnoid space or ventricles

Hemorrhagic Stroke Intracerebral hemorrhage Bleeding within the brain caused by a rupture of a vessel Hypertension is the most important cause Hemorrhage commonly occurs during periods of activity

Hemorrhagic Stroke Intracerebral hemorrhage Manifestations include neurologic deficits, headache, nausea, vomiting, decreased levels of consciousness, and hypertension

Hemorrhagic Stroke Subarachnoid hemorrhage Occurs when there is intracranial bleeding into cerebrospinal fluid-filled space between the arachnoid and pia mater Commonly caused by rupture of a cerebral aneurysm

Clinical Manifestations Affects many body functions Motor activity Elimination Intellectual function Spatial-perceptual alterations Personality Affect Sensation Communication

Clinical Manifestations Brain attack Term increasingly being used to describe stroke and communicate urgency of recognizing stroke symptoms and treating their onset as a medical emergency

Clinical Manifestations Motor Function Most obvious effect of stroke Include impairment of Mobility Respiratory function Swallowing and speech Gag reflex Self-care abilities

Clinical Manifestations Motor Function An initial period of flaccidity may last from days to several weeks and is related to nerve damage Spasticity of the muscles follows the flaccid stage and is related to interruption of upper motor neuron influence

Clinical Manifestations Communication Patient may experience aphasia when a stroke damages the dominant hemisphere of the brain Aphasia is a total loss of comprehension and use of language

Diagnostic Studies When symptoms of a stroke occur, diagnostic studies are done to Confirm that it is a stroke Identify the likely cause of the stroke CT is the primary diagnostic test used after a stroke

Diagnostic Studies Additional studies Complete blood count Platelets, prothrombin time, activated partial thromboplastin time Electrolytes, blood glucose Renal and hepatic studies Lipid profile

Collaborative Care Prevention Goals of stroke prevention include Health management for the well individual Education and management of modifiable risk factors to prevent a stroke

Collaborative Care Prevention Antiplatelet drugs are usually the chosen treatment to prevent further stroke in patients who have had a TIA Aspirin is the most frequently used antiplatelet drug

Collaborative Care Prevention Surgical interventions for the patient with TIAs from carotid disease include Carotid endarterectomy Transluminal angioplasty Stenting Extracranial-intracranial bypass

Collaborative Care Acute Care Interventions – Initial Ensure patient airway Remove dentures Perform pulse oximetry Maintain adequate oxygenation IV access with normal saline Maintain BP according to guidelines

Collaborative Care Acute Care Interventions – Initial 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

Collaborative Care Acute Care Interventions – Ongoing Monitor vital signs and neurologic status Level of consciousness Motor and sensory function Pupil size and reactivity O2 saturation Cardiac rhythm

Collaborative Care Acute Care Recombinant tissue plasminogen activator (tPA) is used to Reestablish blood flow through a blocked artery to prevent cell death in patients with acute onset of ischemic stroke symptoms

Collaborative Care Acute Care Thrombolytic therapy given within 3 hours of the onset of symptoms ↓ disability But at the expense of ↑ in deaths within the first 7 to 10 days and ↑ in intracranial hemorrhage

Collaborative Care Acute Care Surgical interventions for stroke include immediate evacuation of Aneurysm-induced hematomas Cerebellar hematomas (>3 cm)

Collaborative Care Rehabilitation Care After the stroke has stabilized for 12-24 hours, collaborative care shifts from preserving life to lessening disability and attaining optimal functioning Patient may be transferred to a rehabilitation unit