Autor: Kill009 • June 4, 2011 • 2,020 Words (9 Pages) • 760 Views
Running head: Cerebrovascular Accidents
Name of College
A cerebrovascular accident (CVA), also known as a stroke, occurs when the blood supply to the part of the brain is interrupted. Strokes are currently the third leading cause of death and leading cause of serious long term disability in the United States (National Stroke Foundation). Strokes affect people of any race, gender, or age group. Fortunately, up to 80% of strokes are preventable through lifestyle modifications. Conventional medicine has come a long way in the treatment of cerebrovascular accidents, but complementary and alternative modalities have been increasingly incorporated to improve the condition of the whole person.
A cerebrovascular accident begins with an infarction in the brain. An infarction is the process of tissue death resulting from the loss of the tissues blood supply. The loss of the blood supply robs the brain cells of oxygen and nutrients, as well as the cells ability to rid itself of waste material. A central area of necrosis develops as cells begin to die. The brain tissue surrounding the area of necrosis becomes inflamed. Brain function is immediately impaired in affected area of the brain. Cerebral edema and the area of infarct continue to increase over a 48 to 72 hour period. The brain tissue in the area of the infarct actually begins to liquefy, leaving a cavity within the brain.
Causes of Cerebrovascular Accidents
The most common type of ischemic stroke is caused by an atheroma, which is a gradual narrowing of the lumen of an artery. This type of CVA is also called a thrombotic stroke. This occurs as fatty deposits and cholesterol builds up in the blood vessel. This process usually occurs in the larger arteries such as the carotid. The second type of ischemic stroke is caused by an embolus. This type of stroke is caused by a sudden obstruction, usually because of a blood clot that has broken off from an atheroma. The clot travels through the blood stream until it lodges in a smaller blood vessel causing an interruption of the blood supply to the brain. These emboli usually originate from the left ventricle of the heart because of left sided congestive heart failure or prosthetic valves. Although most emboli are blood clots, an embolus can be caused by infection, air, tumor, or fat.
Hemorrhagic strokes are much more severe. This type of stroke only makes up 13% of all strokes, yet hemorrhagic strokes account for 30% of stroke fatalities (National Stroke Foundation). This type of stroke is caused when a blood vessel burst. Not only does it affect large portions of both hemispheres of the brain, it greatly increases intracranial pressure. The most common cause is long standing high blood pressure and cerebral aneurysms. An aneurysm is a thin or weakened portion of a blood vessel wall that can be present at birth or develop over a long period of time (National Stroke Foundation).
There are five risk factors for cerebrovascular accidents that the patient has no control over. First, as an individual grows older, the chance of a CVA occuring increases. The chance of a stroke occurring doubles every decade after the age of 55 (National Stroke Foundation). Strokes affect both men and women. Although CVA's are more common in men, more women die as a result of a stroke. African Americans, Hispanics, and people from an Asian/Pacific descent have a higher risk of experiencing a stroke than Caucasians. The chances of an individual developing a stroke increase if a parent or sibling has had a stroke (Sorrentino). Finally, if the patient has experienced a transient ischemic attack or cerebrovascular accident, the chances of a stroke occurring increases 25% to 40% over the following five year period (National Stroke Foundation). These factors do not condemn an individual to a stroke in the future, but they do emphasize the importance of making lifestyle changes to deal with risk factors that the individual can control.
The following six factors for cerebrovascular accidents can be influenced by dietary and lifestyle changes. First, hypertension damages and weakens blood vessels which promotes clot formation and increases the chance that a vessel may burst (Sorrentino). Hypertension is the leading cause of strokes, increasing the odds of having a stroke 4 to 6 times (National Stroke Foundation). People with hypertension often have no signs or symptoms, so it is important for individuals to have their blood pressure checked regularly. Second, individuals with elevated cholesterol have a greater chance of having a stroke. Elevated blood cholesterol increases the deposits of fatty materials on arterial walls (Sorrentino). Diabetes is another risk factor for cerebrovascular accidents. Blood vessels are damaged as a result of the disease process of diabetes. People with diabetes are 2 to 4 times more likely to have a stroke than individuals who do not have diabetes. Cerebrovascular accidents and heart disease kill 2 out of 3 individuals with diabetes (National Stroke Foundation). Obesity is a risk factor for cerebrovascular accidents. Obese individuals are more likely to have high blood pressure, high cholesterol, heart disease, and diabetes; all of which are risk factors for cerebrovascular accidents. Smoking damages blood vessels, speeds up the clogging of arteries, raises blood pressure and makes the heart work harder (National Stroke Foundation). People that smoke are twice as likely to experience a stroke as non-smoking individuals. Finally, women who use oral contraceptives have a greater risk of experiencing a stroke. Women with several risk factors for cerebrovascular accidents should at least discuss other options with a physician.
Signs and Symptoms
Initial signs and symptoms come on suddenly. First, numbness and weakness of the face, arm or leg. This weakness is likely to affect only one side of the body. Second, sudden confusion and/or trouble talking to or understanding others is another symptom. The third symptom is trouble seeing in one or both eyes. Trouble walking, dizziness, loss of balance or coordination are all warning signs of CVA's.