Strokes
(Cerebral Embolism, Hemorrhage, or Thrombosis; Cerebrovascular Accident; Subarachnoid Hemorrhage)
A stroke occurs when a portion of the brain is deprived of blood, resulting in ischemia or even tissue death. More than 500,000 Americans suffer a stroke each year, about one every minute. Although the stroke death rate has been cut in half over the last 25 years, the affliction still claims 144,000 lives annually, making it the third leading cause of death in the United States (after heart attacks and cancer). Strokes are also a major cause of serious disabilities, which include varying degrees of paralysis, speech problems, visual disturbances, and impaired memory.
Men suffer a slightly greater number of strokes than women, but women account for 60 percent of the deaths. Strokes are more widespread, more severe, and twice as likely to be fatal for African-Americans of both sexes than for Caucasians.
Most strokes fall into one of the following categories:
Cerebral thrombosis, the most common type. It occurs when a blood clot, or thrombus, forms in an artery supplying blood to the brain and is often preceded by mini-strokes, also called transient ischemic attacks or TIAs.
Cerebral embolism, which accounts for 5 to 14 percent of strokes. It occurs when an embolus (wandering clot) forms in the body, travels through the bloodstream, and lodges in the brain.
Cerebral hemorrhage, which accounts for 10 percent of strokes. It is caused by the rupture of a weakened blood vessel, or aneurysm, in the brain. Subarachnoid hemorrhage, which is responsible for 7 percent of strokes. Often the result of an injury, a burst blood vessel bleeds into a space between the brain and skull, rather than inside the brain itself.
Although strokes appear to strike out of the blue, contributing factors are well-known. Poorly controlled high blood pressure greatly increases the risk, as does atherosclerosis, narrowing of blood vessels by fatty deposits. Heart disease, diabetes, excessive red blood cells, obesity, and high blood cholesterol all raise susceptibility to stroke. Other risk factors include such habits as smoking and moderate-to-heavy alcohol use (defined as two or more drinks a day). Women who both smoke and take birth control pills also suffer a higher incidence of strokes. In addition to race, risk factors beyond ones control include advancing age and a family history of strokes.
Warning Signs of a Stroke
Seek immediate medical attention if any of these symptoms develop, even if they then disappear. Temporary symptoms may be due to a mini-stroke, or a transient ischemic attack (TIA), a common precursor to a full-blown stroke. Sudden weakness or numbness of the face, arm, or leg on one side of the body.
- Sudden dimness or loss of vision, especially in one eye.
- Loss of speech or difficulty understanding speech.
- Unexplained dizziness, a sudden fall, or loss of coordination.
- Confusion and unusual behavior.
- Sudden severe headache unlike any previous one.
Diagnostic Studies and Procedures
A doctor will immediately assess vital signs -- blood pressure, heart rate, respiration -- and listen for turbulent sounds, or bruits, in the necks carotid arteries and in other key blood vessels. A suspected stroke calls for immediate neurological evaluation, including assessment of consciousness, orientation, memory, coordination, and vision, hearing, and other sensory responses. Blood studies will be ordered and an electrocardiogram taken, especially if a disturbed heart rhythm is suspected.
The most important diagnostic study, however, is MRI or a CT brain scan to look for cerebral bleeding or blockage. Angiography can pinpoint blocked vessels and reveal damaged areas of the brain. In this procedure, radioactive dye is injected into a vein in the arm and then followed with a camera as it flows through the brain.
Other possible tests include Doppler ultrasound, for studying blood flow through the carotid arteries and other vessels; and carotid phonoangiography, in which a sensitive microphone is used to listen for bruits. An echocardiogram may be ordered if a doctor 9 suspects the stroke is due to a clot that has traveled from the heart to the brain.
Medical Treatments
Intensive treatment within the first six hours after the onset of symptoms is critical in limiting the damage of a stroke. If stroke is due to a thrombus or embolus, clot-dissolving drugs may be administered, as well as heparin or similar medications to prevent more clots from forming. Other drugs may be given to lower blood pressure, steady the heartbeat, and prevent brain swelling.
In some cases, surgery is performed to remove accumulated blood or to repair a ruptured artery or aneurysm.
As soon as the patient's condition is a stabilized, attention turns to rehabilitation, which involves a combination of medical and alternative therapies. The sooner rehabilitation begins, the greater the chance of a good recovery.
After a TIA, the goal of treatment is to prevent a full-blown stroke. Aspirin or other drugs that inhibit clot formation will be given. If the carotid artery is severely clogged, an endarterectomy -- a surgical procedure is which an occluded carotid artery is cleared of fatty deposits -- may be considered. There is increasing emphasis on stroke prevention For example, control of high blood pressure can reduce stroke risk by 50 percent or more. Treatment of atrial fibrillation, a type of cardiac arrhythmia often ignored because it usually produces only minor symptoms, also lowers the risk of a stroke.
Numerous studies have shown that a regimen of low-dose aspirin -- typically, a baby aspirin or one regular aspirin a day -- cuts the incidence of stroke. A doctor should be consulted first, however, because aspirin can increase the risk of hemorrhagic stroke, especially if a person has high blood pressure.
Alternative Therapies
Rehabilitation is a team effort that usually involves a neurologist, a physiatrist (a physician who specializes in rehabilitative treatment), and numerous therapists. Increasingly, a combination of conventional and alternative therapies is used to help patients regain lost function. New York University's renowned Rusk Institute of Rehabilitative Medicine employs the following alternative modalities in addition to conventional medicine.
Acupuncture. Doctors are studying the value of this ancient Chinese practice as a means of stimulating nerve pathways and restoring lost function.
Music Therapy. Therapists use music to improve mood, encourage movement, and help patients regain memory. Because the brain programs and remembers music differently than it processes language, a patient who has difficulty speaking or is suffering memory loss may be able to hum a melody or recall an incident associated with a particular song. As rehabilitation progresses, dance therapy may be added to improve coordination.
Physical and Occupational Therapy. As noted earlier, physical therapy should begin as soon as the immediate crisis is past. Initially, passive range-of-motion exercises, in which a therapist moves the patient's limbs, are used to keep muscles limber and help prevent clots from forming. As nerve function returns, the patient assumes a more active role in these exercises. In some cases, rehabilitation exercises are performed in water, especially if the patient is unable to walk.
Occupational therapy also begins as soon as possible. Partially paralyzed patients learn new approaches to self-care, which may entail using special eating utensils and grooming devices. Patients also learn how to use a cane or, if unable to walk, a wheelchair.
Stroke rehabilitation often takes years; therefore, patients (and family members) should expect to continue working with various therapists.
Speech Therapy. These therapists can help patients relearn speech and improve memory, often by using tape recorders, computers, and other devices.
Self-Treatment
Stroke recovery varies considerably, some patients who initially are totally paralyzed recover fully, while others become increasingly helpless. Experts stress that all family members play an indispensable role in helping the patient recover. Optimism, patience, and understanding are vital, but it is also important to resist the temptation to help too much; instead, encourage the patient to be as independent as possible.
A stroke often alters behavior and personality, but the nature of change depends upon the side of the brain that is damaged. Left-brain injury usually results in speech problems and a more cautious, less organized, and slower behavior style. Because they have difficulty in communicating, these patients often appear to be more handicapped than they actually are. However, if a task is broken down into simple steps, they are often able to make great progress.
In contrast, a person who suffers right-brain damage may be able to speak, understand, and respond more quickly, but may have difficulty with tasks requiring spatial and perceptual skills. These patients, as well as their caregivers, lend to overestimate their capabilities, resulting in frustration when they fail. It is important to provide cues and encouragement, but its also necessary to protect the patient from falls or self-injury.
Emotional ups and downs are to be expected after a stroke. Crying is especially common, but it may not reflect sadness -- brain damage may be responsible. If the person stops crying immediately when you call his name or snap your fingers, the crying probably stems from organic causes rather than sadness. Similarly, do not assume that bursts of laughter signal happiness; they also may reflect brain damage.
To cope with these and other aspects of stroke recovery, specialists recommend joining a stroke survivors support group, which can be as beneficial for family members as for the patient.
Other Causes of Stroke Symptoms
Head injuries can cause paralysis, disorientation, and other symptoms that characterize stroke. Memory loss, visual disturbances, and gait abnormalities can be caused by alcohol or drug abuse, as well as some medications. Other disorders that can mimic symptoms like those of a stroke include complicated migraine headaches, seizures, multiple sclerosis, and encephalitis, an inflammation of the brain.