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Product Details
| ISBN-13: | 9781936374717 |
|---|---|
| Publisher: | Addicus Books |
| Publication date: | 02/01/2012 |
| Sold by: | Barnes & Noble |
| Format: | eBook |
| Pages: | 152 |
| File size: | 876 KB |
About the Author
Read an Excerpt
The Stroke Recovery Book
A Guide for Patients and Families
By Kip Burkman, Bob Hogenmiller
Addicus Books, Inc.
Copyright © 2010 Kip Burkman, M.D.All rights reserved.
ISBN: 978-1-936374-71-7
CHAPTER 1
The Brain and How Strokes Occur
Imagine, for a moment, you're going through your day and suddenly you have a pounding headache and, although you're in familiar surroundings, nothing looks familiar.
Suddenly, you're aware of a spreading warmth between your legs. You've wet your pants. You've also fallen to the floor. No matter how hard you struggle to get up, you can't. Neither your arm nor your leg will move. You try calling for help, but the words coming out of your mouth are gibberish. If you're alone, a frightening thought overwhelms you: What if no one finds me?
This scenario describes what it might be like if you suffer a stroke. A frightening proposition, indeed, especially in those first hours and days. You wonder if you will live. Will you be impaired? How long will rehabilitation take? How complete will recovery be? These are just a few of the questions that might race through your mind or the minds of loved ones.
Unfortunately, there are no standard answers to these questions. However, for most individuals, the ability to understand and adapt to this new reality depends largely on their attitudes and efforts as well as on support from family, friends, healthcare professionals, and caregivers.
In this chapter, we'll discuss the complexities of strokes and how they occur. In order to better understand how strokes affect the brain, let's first review the basics of how the brain works.
Brain Anatomy
The upper brain, or cerebrum, is divided into two hemispheres. The cerebrum contains the cortical area, used for thinking, and the subcortical area, a complex network of nerves that act as relay centers and linking pathways. Each hemisphere has four separate lobes: frontal, parietal, temporal, and occipital. Frontal lobes — located in the front of the brain — control thinking, behavioral functions, and body movement. Parietal lobes assist in sensation, concrete thinking (such as math), abstract thinking, vision-space orientation, and language. The temporal lobe is part of the emotional and memory center and also contains language functions. The occipital lobe is the part of the brain that interprets what we see.
The back part of the brain, the cerebellum, controls balance and coordination. Under the cerebrum lies the brain stem. It controls involuntary and automatic survival processes we don't need to think about, such as heart rate, body temperature, breathing, sleeping cycles, and the regulation of some hormones.
How Blood Flows to the Brain
Blood moves from the heart to the brain through the large carotid arteries, which travel up each side of the neck along the windpipe. Once inside the skull, the carotid arteries divide into front and side branches. These blood vessels supply the front two-thirds of the brain's outer surface. The vertebrobasilar arteries travel upwards and serve this region as well as the coordination centers and the brain stem.
How the Brain Sends Signals
The wiring of nerves in the brain is complex. Although the two hemispheres of the brain look identical, they handle separate functions. Each hemisphere controls movement and sensation on the opposite side of the body. For example, if you put your left hand under hot running water, the right cerebral cortex interprets the stimulus as pain. To reach forr an ice cream cone with your right hand, the left side of the brain generates a signal. The left part of the brain is dominant in right-handed people, while the right portion of the brain is dominant in left-handed individuals.
Stroke: "Brain Attack"
A stroke is a "brain attack" in the same way a blockage of blood flow to the heart is a "heart attack." A stroke occurs when an area of the brain is deprived of blood flow. Most commonly, this happens when blood vessels are blocked by a clot or have become too narrow for blood to pass through. A stroke may also occur when a blood vessel bursts and leaks blood into the brain, causing damage. A lack of blood pumped to the brain, the result of a heart attack, may also cause a stroke.
When blood flow to the brain stops suddenly, a person will fall unconscious in about twelve seconds. Since the brain relies on the glucose and oxygen carried by blood cells for energy, brain cells will begin to die after about four minutes without these nutrients. This is a critical situation. Unlike other body tissues that have the ability to repair themselves over time, brain tissue is highly specialized and is less able to recover.
If Someone Is Having a Stroke
Are you aware of the signs of a stroke? Do you know what action to take if you think a loved one or friend is having a stroke?
Symptoms include: numbness or weakness in the face or limbs, sudden confusion and trouble speaking, trouble seeing, sudden dizziness or loss of balance, and sudden headache. Getting emergency medical care quickly is critical. The majority of strokes (80 percent) occur as a result of blood clots in the brain. Individuals having this type of stroke are often candidates for a clot-busting drug called tPA, tissue plasminogen activator. The drug can significantly reduce brain damage and the resulting disability after a stroke. However, the drug must be given within three hours of the onset of symptoms. Therefore, it's also important to tell hospital personnel when the stroke patient's symptoms started.
Unfortunately, most people delay calling for help, according to a 2010 study completed by researchers at the Michigan Department of Community Health. The researchers reported that in a survey of 4,800 people, only a fraction said they would call 911 if they observed a relative or friend showing symptoms of stroke.
Remember also that you may be the person who needs to call 911. A stroke can injure a person's brain, and he or she may not be able to tell you of their symptoms. Therefore, the best thing you can do if you think someone is having a stroke is to call for an ambulance immediately. The difference can save a life and reduce the chance for permanent disability.
Those conducting the Michigan study also urge the public to call 911 for an ambulance rather than transport a stroke victim themselves to a hospital emergency room. Patients who are transported by ambulance can begin receiving treatment immediately upon the arrival of emergency medical personnel. Also, patients transported by ambulance reach hospitals sooner and receive treatment sooner than those who are taken to the hospital by relatives or friends.
Major Causes of Stroke
Thrombosis
The leading cause of stroke is thrombosis, or blood clots. Clots develop gradually when the inner lining of blood vessels become clogged with the build-up of cholesterol and fatty substances. This clogging is similar to the deposit of lime scale in water pipes: Eventually enough scale accumulates to narrow or totally shut off the flow of water. In blood vessels, a build-up of cholesterol from years of eating a high-fat diet may have the same effect. Progression toward a stroke may be either sudden or incremental. Symptoms and conditions may alternately worsen or improve over hours or weeks.
Embolism
The second major cause of stroke, embolism, occurs when a clot formed in a blood vessel somewhere in the body breaks off, enters the brain's circulatory system, and travels until it encounters an artery it can't pass through. The middle cerebral artery, located in the middle portion of the brain, is most often affected by emboli. Clots may be caused by platelets, components of the blood's clotting mechanism, or by cholesterol in the neck arteries that softens and breaks off into a blood vessel. When a clot lodges in a blood vessel, the area of the brain served by that blood vessel may die. Clots sometimes break up into smaller pieces quickly enough to restore the blood flow. Some embolism patients experience a secondary problem: bleeding from damaged vessels where the emboli lodge.
The heart, as well as the neck arteries, is a major source of clots. Clots from the heart can arise from abnormal heart rhythms, heart attacks, the surgical placement of artificial heart valves, heart bypass operations, infections inside the heart, damage to the heart valves from rheumatic heart disease, or mitral valve prolapse (valves collapse inward, allowing blood to enter a chamber inappropriately) If a large clot that originates in the heart fragments, the brain may be showered with small pieces, causing multiple patterns of brain damage. These patterns often help a physician identify a stroke caused by emboli.
A physician may perform a test, a transthoracic or transesophageal echocardiogram, to help determine whether an abnormality inside the heart is responsible for emboli. This procedure involves placing a special probe into the esophagus, the swallowing tube in the throat, and bouncing sound waves off the back of the heart to reveal pictures of the heart's structures and function. These pictures will show clots inside the heart that may be responsible for the stroke.
Hemorrhages
Hemorrhage is the third major cause of stroke. Hemorrhages can be caused by aneurysms, weakened blood vessels that form bubble-shaped projections and then break. A subarachnoid hemorrhage results from bleeding in the deeper cavities of the brain. An intracerebral hemorrhage occurs when a blood vessel bursts, leaking blood into the firm tissue of the brain. Pressure or blood vessel spasm from the bleeding can pinch surrounding blood vessels, shutting off more blood flow and producing further stroke effects.
Hemorrhagic strokes are the most deadly, due to the pressure they can produce on vital parts of the brain. Patients who survive bleeding strokes for more than thirty days often have fairly good functional outcomes. The most common cause of stroke by hemorrhage is poorly controlled high blood pressure, also known as hypertension. Other causes include malformations of blood vessels inside the brain, blood clotting diseases, some types of liver disease, and brain tumors.
Hypotension
The fourth major cause of stroke, hypotension, occurs when blood pressure falls to dangerously low levels. Not enough blood is being pumped to the brain. The medical term for this resulting brain damage is anoxic encephalopathy. These patients differ from all other stroke patients in that all, not just part, of the brain may lose its blood supply. This can happen in cases of severe heart failure, with certain abnormal heart rhythms, and in some heart attacks when the heart fails to adequately pump blood. Some survivors of cardiopulmonary resuscitation (CPR) may also fall into this group.
Blood Clotting Abnormalities
Blood clotting abnormalities are responsible for a far less common type of stroke. In these cases, the body's balance between making blood clots and breaking them down shifts, with an increased tendency to make clots that are large enough to cause strokes. Medical scientists are still studying the reasons for this imbalance.
Transient Ischemic Attacks (TIA)
A transient schemic attack (TIA), often called a mini-stroke, is a temporary blockage of an artery. Neurological symptoms go away within twenty-four hours, depending on which artery is blocked. TIAs leave no permanent brain tissue damage. When a person with TIA symptoms arrives in a hospital emergency department, it may initially be difficult for doctors to tell if the patient is having a TIA or a full-blown stroke. The patient will likely be admitted to the hospital for further examination.
However, TIAs are often warnings of strokes to come. An estimated 40 percent of people who suffer TIAs ultimately have strokes, often within a year. People who have several TIAs within a short period of time have a higher risk of developing full-blown strokes. Still, not all TIAs result in stroke. Some people have TIAs that will disappear. Others have TIAs that persist but never progress to stroke. Clearly, medical evaluation at the earliest stage, when brain damage is reversible, is the best way to prevent permanent brain damage.
Location of Strokes in the Brain
Strokes are labeled according to the area of the brain that is damaged. For example, if the right hemisphere of the brain loses its blood supply, a right hemisphere stroke is said to have occurred. A stroke on the left side of the brain is referred to as a left hemisphere stroke. If an individual suffers a right hemisphere stroke, the left side of the body will be affected. If a stroke occurs in the left side of the brain, the right side of the body will be affected.
Four areas of the brain (artery blood-flow centers) are most commonly affected by stroke. A list of these areas follows, along with an explanation of the deficits that frequently result from these strokes. Deficits are deficiencies in mental or physical functions that result from damage to the brain. Common deficits include weakness or paralysis; loss of sensation; problems walking or speaking; and difficulties with activities of daily living (ADLs) such as dressing, eating, speaking, and grooming.
Middle Cerebral Artery Stroke
A stroke occurring in the middle cerebral artery may cause:
• loss of feeling on the opposite side of the body
• the arm to usually be weaker than the leg
• significant drooping of the lower half of the face, and drooling
• loss of strength, varying from slight weakness to complete paralysis
• loss of vision, or blind spots
• communication problems, including the inability to understand and produce language
• confusion differentiating between left and right
Anterior Cerebral Artery Stroke
Damage to the anterior cerebral artery may cause:
• weakness or paralysis on the opposite side of the body
• the leg to usually be weaker than the arm
• trouble with bowel and bladder control
• opposite-side sensation loss
• intellectual disturbances, including repetitive thought and speech
• disorientation (who and where the patient is and problems understanding aspects of time)
• confusion, forgetfulness, distractibility, and slowed thinking
• an inability to perform tasks when asked, even though the patient has the physical ability to perform the task automatically at other times (apraxia)
• facial weakness
• problems with grasp reflex so strong that the patient cannot let go of objects
Posterior Cerebral Artery Stroke
Strokes occurring in the posterior cerebral artery affect the back part of the brain. This artery serves a wide area of brain tissue. Deficit patterns vary depending on which areas are impacted, but may include:
• blind spots on the side opposite where the brain damage occurred
• memory problems and difficulty reading
• severe loss of touch sensation
• burning sensation in the limbs (thalamic pain syndrome)
• weakness and involuntary movement disorders
• lack of coordination (ataxia)
• cortical blindness, of which the patient is not fully aware
Brain Stem Stroke
Blockages in the vertebral and basilar arteries at the base of the brain may damage the brain stem. This particularly vulnerable area includes tightly packed nerve cells, similar to the filaments in a telephone cable. The brain stem controls automatically regulated functions such as heartbeat and breathing. Damage to this area may result in coma or death. Depending on which small blood vessel is blocked, numerous combinations of deficits and syndromes may occur, including:
• sensory loss
• weakness on one side of the body and poor coordination
• swallowing difficulties
• loss of emotional control
• slurred speech
• visual problems, double vision
• dizziness/vertigo
• seizures
• headaches
(Continues...)
Excerpted from The Stroke Recovery Book by Kip Burkman, Bob Hogenmiller. Copyright © 2010 Kip Burkman, M.D.. Excerpted by permission of Addicus Books, Inc..
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.
Table of Contents
Acknowledgments vi
Introduction vii
1 The Brain and How Strokes Occur 1
2 Impairments Caused by Stroke 14
3 Aphasia: Speech and Language Disruptions 21
4 Hemiplegia: Weakness on One Side 28
5 Dysphagia: Swallowing Difficulties 37
6 Bladder, Bowel, and Sexual Problems 45
7 Other Medical Complications Caused by Stroke 54
8 Recovering from a Stroke 64
9 Rehabilitation 71
10 Care after a Stroke 80
11 Reducing Your Risk of Stroke 96
12 Care for Caregivers 104
Appendix 113
Resources 114
Glossary 120
Index 135
About the Author 144