C H A P T E R 1 8

STROKELAWRENCE M. BRASS, M.D.

INTRODUCTION

Stroke is a form of cardiovascular disease affectingthe blood supply to the brain. Also referred to ascerebrovascular disease or apoplexy, strokes actuallyrepresent a group of diseases that affect about oneout of five people in the United States. When physi-cians speak of stroke, they generally mean there hasbeen a disturbance in brain function, often perma-nent, caused by either a blockage or a rupture in avessel supplying blood to the brain.

In order to function properly, nerve cells withinthe brain must have a continuous supply of blood,oxygen, and glucose (blood sugar). If this supply isimpaired, parts of the brain may stop functioningtemporarily. If the impairment is severe, or lasts longenough, brain cells die and permanent damage fol-lows. Because the movement and functioning of var-ious parts of the body are controlled by these cells,they are affected also. The symptoms experienced bythe patient will depend on which part of the brain isaffected.

Stroke is a major health problem in this country.Nearly 500,000 people in the United States have astroke each year, and nearly a third of these peopledie during the first few months after their stroke, Ofthose who survive, about 10 percent are able to returnto their previous level of activity, about 50 percentregain enough function to return home and carry onwith only limited assistance, and about 40 percentremain institutionalized or require significant assis-tance in caring for themselves.

While the incidence of stroke has decreased agreat deal over the past few decades, there is evi-dence that this trend may be leveling off.

Stroke is costly. The cost in human terms, to pa-tients and their families, is impossible to estimate. Thecost to the U.S. economy—in terms of medical careand lost income—amounts to over $25 billion eachyear.

Although stroke is often viewed as a disease of theelderly, it sometimes affects younger individuals. Theincidence of stroke does increase with age, but nearlya quarter of all strokes occur in people under the ageof 60.

Stroke patients are often cared for by neurologists,because of the complex nature of the symptomscaused by damage to the brain. However, strokes arevery closely related to heart disease. Heart attacks(myocardial infarctions) and stroke are both causedby diseases of the blood vessels. They share many ofthe same risk factors, and modifying these risk factorsmay reduce the possibility of stroke. Many of the ther-apies used for cardiac disease show promise for sometypes of stroke. Finally, people who already have cor-onary disease may be at greater risk for stroke, andvice versa.

HOW THE BRAIN FUNCTIONS

To understand the signs and symptoms of stroke andwhy they can differ from patient to patient, it is nec-essary to understand a little about the brain and how

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it functions. There are literally thousands of possiblesymptoms that can result from a stroke, dependingon which blood vessels and parts of the brain areinvolved. It is also important to realize that except fora brief period after birth, brain cells are unable todivide and form new cells. When brain cells die, theyare not replaced. This is part of the reason for thelimited ability of the brain to repair itself after injury,and why recovery from stroke is only partial in manycases. While someone who suffers a heart attack, forexample, can lose 10 percent of heart tissue and stillrun a marathon, losing 10 percent of the tissue incertain parts of the brain can result in a devastatingdisability.

The human brain is the most complex structureknown. It is composed of 100 billion nerve cells, calledneurons; each neuron may connect to thousands ofother brain cells. The trillions of connections are nec-essary for the integrative power of the brain. Theyalso control body movements, interpret all sensations(hearing, vision, touch, balance, pain, taste, andsmell), and mediate thought and language. Differentareas of the brain control different functions. (SeeFigure 18.1.)

Although the brain represents only 2 percent ofthe body's weight, it uses about 25 percent of thebody's oxygen supply and 70 percent of the glucose(sugar). Unlike muscles, the brain cannot store nu-

trients, and thus it requires a constant supply of glu-cose and oxygen. If the blood supply is interruptedfor as little as 30 seconds, unconsciousness results;permanent brain damage may follow in as little asfour minutes. The brain’s high metabolic rate, sen-sitivity to changes in blood flow, and dependence oncontinuous blood flow are what can make strokes sodangerous. Figure 18.2 shows the major arteries sup-plying the brain.

The brain can be divided into three areas: brainstem, cerebellum, and cerebrum. The brain stem con-trols many of the body’s basic functions, includingbreathing, chewing, swallowing, and eye move-ments. The major pathways from the cerebrum—thethinking part of the brain—also pass through thebrain stem to the body. The cerebellum, attached tothe back of the brain stem, coordinates movementsand balance.

The cerebrum is divided into two hemispheres, leftand right. In general, the left brain receives input(sensations) from the right side of the body and con-trols movement on the right side, so that a stroke inthe right side of the brain will cause left-sided weak-ness. Conversely, the right brain controls the left sideof the body.

Each side of the cerebrum is further divided intofour lobes. The frontal lobes control motor function,planning, and expression of language. The temporal

Figure 18.2Shown are the major arteries feeding the brain. The carotid and itsbranches (anterior cerebral artery and middle cerebral artery) feedthe front part of the brain and most of the cerebral hemispheres (topof the brain). The vertebral arteries join in the back of the head toform the basilar artery. These arteries and their branches supply thebrain stem, cerebellum, and back parts of the brain.

lobes are involved with hearing, memory, and be-havior. The parietal lobes interpret sensation andcontrol understanding of language. The occipitallobes perceive and interpret vision. The right and theleft sides of the cerebrum are not identical, but ratherhave specialized functions. In almost all right-handedpeople and most left-banders, the left brain is “dom-inant” and performs most language functions. Theright side of the brain controls the abilities to under-stand spatial relations and recognize faces, as well asmusical ability. It also helps focus attention.

RISK FACTORS AND STROKEPREVENTION

Given the devastating deficits often associated witha stroke, the need for prevention is obvious. Many ofthe risk factors for stroke (see box, “Stroke Risk Fac-

tors”) can be treated or modified. Doing so may pre-vent an initial stroke or recurrent strokes, as well asdecrease the risk of premature death, which is mostoften the result of coronary disease.

A number of stroke risk factors are the same asthose for heart disease, although their relative im-portance varies. For example, a high blood choles-terol level is a much more significant risk for heartdisease. This distinction is of little practical impor-tance, because both coronary and stroke risk factorsshould be addressed in patients who are at risk for,or who have suffered, a stroke or a transient ischemicattack. (The latter, also called a TIA or a ministroke,is discussed later in this chapter.)

Three of the greatest risk factors for stroke—highblood pressure (hypertension), heart disease, anddiabetes—often do not cause symptoms in their ear-liest stages. For this reason, it is important that alladults, but especially those with a family history ofheart disease or stroke, have regular screening for

Stroke Risk FactorsCharacteristics and life-style

DefiniteCigarette smokingExcessive alcohol consumptionDrug use (cocaine, amphetamines)AgeSexRaceFamilial and genetic factors

PossibleOral contraceptive useDietPersonality typeGeographic locationSeasonClimateSocioeconomic factorsPhysical inactivityObesityAbnormal blood lipids

Disease or disease markersHypertensionCardiac diseaseTIAElevated hematocritDiabetes mellitusSickle cell diseaseElevated fibrinogen concentrationMigraine headaches and migraine equivalentsCarotid bruit

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these and other vascular risk factors. Routine check-ups should begin at age 20 and be repeated at leastevery five years, more frequently in later years or ifwarranted by the results of the initial screening.Blood pressure should be checked more frequently.

HIGH BLOOD PRESSURE

A major risk factor common to both coronary heartdisease and stroke, high blood pressure is present in50 to 70 percent of stroke cases, depending primarilyon the type of stroke. The long-term effects of theincreased pressure damage the walls of the arteries,making them more vulnerable to thickening or nar-rowing (atherosclerosis) or rupture.

There is no specific blood pressure reading that isconsidered normal, but rather a range. Most expertsagree, however, that a reading greater than 140/90mm Hg is abnormal, and anyone with such a readingshould see a physician. But even mild elevations inblood pressure are associated with an increased riskfor stroke. Sometimes mildly elevated blood pressurecan be controlled by life-style modification, but med-ication is often needed. Although the patient may feelno different, control of blood pressure is associatedwith a marked decrease in the occurrence of stroke.(See Chapter 12.)

HEART DISEASE

Just as strokes area strong risk factor for heart dis-ease, heart disease is a strong risk factor for stroke,although only for one type of stroke, ischemic strokes.Heart disease is associated with stroke in two ways.First, damage to the heart (as, for example, from aheart attack) may make it more likely that clots willform within the heart. These clots can break looseand travel to the brain, causing a cardioembolicstroke. Heart disease and stroke are also associatedbecause they are both manifestations of atheroscle-rotic disease in the blood vessels. If the blood vesselsfeeding the heart (the coronary arteries) are diseased,it is likely that arteries to the brain are also affected.

Patients with evidence of coronary artery disease,congestive heart failure, left ventricular hypertrophy(enlargement of the left side of the heart), disease ofthe heart valves, or arrhythmias (irregular heartrhythms) have a several-fold increase in the risk ofstroke.

Several recent studies suggest that people withatrial fibrillation who take daily doses of either aspirinor warfarin (Coumadin) have a reduction of up to 80

percent in their risk of stroke. These findings suggestthat an estimated 20,000 to 50,000 strokes might beprevented each year if all people with this conditionhad prophylactic drug treatment.

SMOKING

Smoking facilitates atherosclerosis and appears to bean independent risk factor for strokes that result froma clot. It also seems to be a risk for strokes that resultfrom cerebral hemorrhage.

Men in Framingham, Massachusetts-a commu-nity studied extensively for cardiovascular disease—who smoked more than 40 cigarettes a day had twicethe stroke risk of men who smoked fewer than 10. Ina large Harvard Medical School study of women, thenumber of cigarettes smoked was found to be directlyrelated to stroke risk. Women smoking more than 25cigarettes a day had a 2.7 times greater risk of strokefrom a clot or embolus and a 9.8 times greater riskof a hemorrhagic stroke. Data from both the Fra-mingham Heart Study and the Honolulu Heart Studyindicate that one can significantly reduce stroke riskby stopping smoking. Five years after they stop, ex-smokers have a stroke risk equal to that of non-smokers.

DIABETES

People with diabetes are at greater risk for stroke,just as they are for heart disease. Women with dia-betes are at an even greater risk than men. High bloodpressure compounds the risk. Although treatment ofdiabetes has not been conclusively shown to reducerisk, it is known that control of high blood sugar (hy-perglycemia) can reduce the severity of cerebral dam-age during a stroke. For this and other reasons,diabetics should keep their blood glucose levels understrict control.

CHOLESTEROL

Studies have found a link between high blood lipidlevels and atherosclerosis in cerebral arteries, but itis still unclear whether high cholesterol levels signif-icantly increase stroke risk. They do, however, in-crease heart disease risk, so efforts should be madeto reduce them.

OBESI’IY AND INACTIVITY

Obesity and a sedentary life-style are risk factors forstroke primarily because they increase the risk of

STROKE

high blood pressure, heart disease, and diabetes.They may also be independent stroke risk factors.Losing weight and following a moderate exerciseregimen can help reverse these risks.

ORAL CONTRACEPTIVES AND ESTROGENREPLACEMENT THERAPYThe role of oral contraceptives in stroke risk is stillinconclusive, primarily because most research haslooked at the effects of high-dose estrogen pills, andmost women now use lower-dose preparations. Es-trogen is believed to promote blood clotting; lower-dose estrogen preparations are thought to minimizethis effect. Because studies have found no increase incurrent risk of stroke or heart attack in women whopreviously used oral contraceptives, it is believed thatthe pill does not promote atherosclerosis.

Several retrospective studies have suggested thatoral contraceptive use is associated with an increasein stroke risk, while other studies have only found asignificant risk of brain hemorrhage in women overage 35 who take the pill and smoke. Smokers whohave migraine headaches and take oral contracep-tives may be at a particularly high risk of stroke. Ex-perts usually advise women who smoke not to useoral contraceptives—or better, to quit smoking.

In contrast, there is evidence to suggest that es-trogen replacement therapy for postmenopausalwomen may slow the atherosclerotic process. In thisgroup the use of estrogens may actually lower therisk of stroke (and heart disease).

HISTORY OF TRANSIENT ISCHEMICATTACKS (TIAs)Researchers are learning that these “ministrokes”may be the most reliable warning of an imminent“full” stroke. Between 10 and 50 percent of strokes,depending on the type, are preceded by TIAs; if nottreated, about one-third of all people who have a TIAgoon to have a stroke within five years, TIAs are alsoindicators of potential coronary heart disease: Eachyear, 5 percent of those who have had at least oneTIA have a heart attack. Anyone who has had a TIAshould do whatever possible to reduce other risk fac-tors. Drug therapy or surgery may be warranted toreduce the risk of subsequent TIAs, . stroke, or heartattack.

HEREDITY AND FAMILY HISTORYThe chance of having a stroke is higher for peoplewho have a family history of this disease. Part of the

risk is due to inherited risk factors and part to family life-styles (eating and exercise habits, for example).

The presence of inherited risk factors does not mean that risk cannot be lowered. In one study, for instance, the hereditable risk for vascular disease was mostly due to a susceptibility to the effects of cigarette smoking. When cigarette smoking was eliminated, the hereditable effect was significantly lowered.

The risk of stroke rises significantly with age. After55, it more than doubles with each passing decade.Each year, about 1 percent of people between ages65 and 74 have a stroke—and 5 to 8 percent of peoplein that age group who have had a TIA go on to stroke.

Although risk associated with advancing age can-not be changed, it is an important factor in assessingstroke risk and planning preventive therapies.

AN EARLIER STROKEBecause the same factors that caused a first strokeare likely to cause a subsequent one, the risk of strokefor someone who has already had one is increased.

CAROTID BRUITA bruit is a noise made by turbulent flow in a bloodvessel that usually can be heard only with a stetho-scope. The most common cause is a narrowing of anartery because of atherosclerosis. Bruits tend to oc-cur in the large arteries of the body, including thecarotid artery in the neck. Even in patients withoutother symptoms, carotid stenosis (narrowing) and ca-rotid bruits are associated with an increased strokerate of 5 percent each year. Over the course of alifetime, the cumulative stroke risk may be quite high.

The increased risk associated with the presence ofa carotid bruit has prompted some physicians to rec-ommend a surgical procedure called carotid endar-terectomy to open the narrowing. Initial results ofthis procedure have proved disappointing in termsof preventing strokes. Patients with asymptomaticbruit should, if possible, be considered for referral toa medical center that has special expertise in cere-brovascular disease and is participating in a well-designed clinical trial.

OTHER RISK FACTORSOther factors influence stroke risk, although to alesser extent. These include an elevated hematocrit

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(number of red cells in the blood), geographic loca-tion (especially the southeastern United States, whichis sometimes called the “stroke belt"), lower socio-economic status, Type A personality (see Chapter 8),use of cocaine and amphetamines, and high alcoholconsumption. Stroke deaths seem to occur moreoften during periods of extreme heat or cold.

TRANSIENT ISCHEMIC ATTACKS(TIAs)

A transient ischemic attack is a localized neurologicalproblem caused by ischemia (decreased blood flow)that completely resolves within 24 hours. Most lastonly a few minutes. People who suffer a TIA oftenpass it off as nothing, especially when it goes awayalmost as quickly as it came. The more neurologistslearn about the cause of TIAs, the more clear it be-comes that a TIA presents a unique opportunity toprevent a stroke.

The importance of a TIA is not in its neurologicalsymptoms-by definition, they disappear. Rather itis that a third of all patients will go on to have a stroke.TIAs represent about 10 percent of all cerebrovas-cular disease. Up to half of patients who suffer anischemic stroke will report having had a TIA, and maynever have sought treatment. TIAs also identify agroup of people at high risk for heart attack. It isimperative that anyone who experiences a TIA con-sult a doctor for both neurological and cardiovascularevaluation. The key is to make the diagnosis and workto lower the risk.

The symptoms of a TIA are similar to those of astroke-weakness or numbness on one side of the body,inability to speak or understand language, or lack ofcoordination-except they don’t last as long. Anycombination of the symptoms described for stroke,lasting more than a few seconds, should be consid-ered as a possible TIA. (See box, “Common WarningSigns of Stroke and Transient Ischemic Attack.”)

One additional common symptom of a TIA is tran-sient monocular blindness, also called amaurosis fu-gax (flight of darkness). This is a brief change ordistortion of vision in one eye that is often describedas a misting, clouding, blurring, spottiness, or thesensation that a blind is being drawn down overthe eye.

The evaluation of a patient for a TIA is similar tothat for a stroke. Most patients will be hospitalized

Common Warning Signs ofStroke and Transient IschemicAttack (TIA)Because brain cells can die very quickly after a

stroke, it is crucial to recognize warning signs ofan impending stroke and get to a hospitalquickly. Since the brain controls hundreds ofactivities, the range of stroke symptoms isbroad. In spite of this, there are severalcommon warning signs of stroke or TIA:

● Sudden weakness or numbness of the face,arm, and leg on one side of the body

● Loss of speech, or trouble speaking orunderstanding speech

● Dimness or loss of vision, particularly in onlyone eye or half of both eyes

● Sudden onset of blurred or double vision

● Unexplained dizziness

● Sudden onset of unsteadiness, lack ofcoordination, difficulty walking, or falling

● Sudden excruciating headache

● Recent change in personality or mentalabilities, including memory loss

Although many of these symptoms can be causedby other diseases, the sudden onset of newneurological symptoms should prompt a personto seek immediate medical attention.

because of the concern of a subsequent stroke andthe need for immediate treatment should one occur.Patients at low risk of stroke and those whose generalmedical condition precludes aggressive treatmentmay be followed on an outpatient basis.

The first step is to consider, and exclude, otherdisease that can mimic a TIA. (See box, “ConditionsThat Can Mimic a TIA.”) Many of these diseases areserious neurological problems that also may requireurgent treatment. After other diseases have been ex-cluded, the physician will try to determine the mech-anism of the TIA in order to help guide decisionsabout treatment. Most TIAs are due to either an em-bolus (blood clot) or restricted blood flow-oftencaused by a narrowing in the carotid artery. BriefTIAs (lasting less than 10 minutes) are commonly as-sociated with carotid stenosis (artery narrowing),while longer-duration TIAs (lasting more than onehour) are more often caused by embolism.

If a TIA is due to restricted blood flow because ofa carotid artery stenosis, surgery may be indicated.

Hypoglycemia (low blood sugar)Other’ forms of strokeBrain tumorArteriovenous malformationMultiple sclerosisIncipient syncope (fainting)Orthostatic hypotension (low blood pressure)Cardiac arrhythmia (irregular heartbeat)AmnesiaNarcolepsy/cataplexy (disorders of excessive

sleepiness)Intracranial inflammation (e.g., brain infection)Periodic paralysisPressure neuropathy (nerve compression)Dizziness of uncertain causeAnxietyHyperventilationLabyrinthine (inner-ear) disease

If it is due to an embolus from the heart (as may occurwith various abnormal heart rhythms), even if thereis a carotid stenosis, surgery may not be appropriate.(For treatment options, see the discussion of long-term treatment of TIA and stroke elsewhere in thischapter.)

ISCHEMIC STROKEThere are two broad categories of stroke: ischemicand hemorrhage. Ischemic strokes are caused by a

Figure 18.3

STROKE

lack of blood flow to the brain and account for about70 percent of all strokes. (See Figure 18.3.) Hemor-rhagic strokes, discussed later in this chapter, arecaused by bleeding into the brain or adjacent tissues.

Within the category of ischemia, there are severalsubcategories of stroke. One common type, called ce-rebral atherothrombosis (also referred to as large ar-tery disease), is caused by a clot (thrombus) thatblocks blood flow in an artery. The narrowing leadsto a low flow state referred to as watershed (or distalfield) ischemia. (See Figure 18.4.) If the resulting lackof oxygen results in death of brain tissue and per-manent damage, the term cerebral infarction is used.

Clots usually do not occur in healthy arteries, buttend to form at or adjacent to an area of a vesseldamaged by atherosclerosis. In the atheroscleroticprocess, plaque—an amalgam of fatty substances,cholesterol, waste products of cells, calcium, and ablood-clotting material called fibrin-builds up asthick, irregular deposits on the inner lining of an ar-tery. The irregular surfaces that plaque deposits cre-ate provide ideal places for clots to form and grow.In some cases, plaque deposits themselves can growso large that they obstruct the opening (lumen) of theblood vessel and block the flow of blood. Surgery isoften indicated to open these arteries.

Atherothrombic strokes are often preceded byTIAs, and they tend to occur at times when bloodpressure is low—at night during sleep, or early in themorning before major activities start.

Another kind of ischemic stroke involving a clot iscalled a cerebral embolism or embolic stroke. Thistype is caused by a wandering clot (embolus) thatforms in one part of the body, breaks loose (in wholeor part), and travels in the bloodstream until it lodgesin an artery in the brain or in a vessel leading to thebrain. (See Figure 18.5.) Emboli can be formed from

MAJOR CARDIOVASCULAR DISORDERS

Branches of anterior cerebral arteries

Figure 18.4A watershed (or distal field) stroke is the result of narrowingof the large arteries feeding the brain.

Figure 18.5An embolic stroke is the result of a blood clot that forms in anotherpart of the body and travels in the bloodstream until it lodges in anartery in the brain.

Branches of anterior cerebral arteries

Branches of anterior cerebral arteries

Figure 18.6A lacunar stroke is the result of the complete blockage of anarteriole, the very small end of an artery that penetrates deep intothe brain.

calcium, cholesterol, air, blood proteins, platelets, orby-products of an infection of the heart’s inner lining(endocarditis). (See Chapter 15.) It is believed thatmost ernbolic strokes involve clots from the heart orthe carotid arteries.

The most common cardiac conditions associatedwith emboli are atrial fibrillation, valvular disease, thepresence of a prosthetic heart valve, endocarditis,congestive heart failure, and myocardial infarction.In atrial fibrillation, the two upper chambers of theheart (atria) quiver rather than beat effectively. Be-cause blood is not pumped out of the atria (upperpart of the heart) completely it tends to pool and formclots. One-third of all people with atrial fibrillationwill have a stroke at some time, and the majority ofthese strokes will be embolic. Embolic strokes areprobably the most common of ischemic strokes.(Many that have no proven cause are thought to becaused by embolism.) The use of anticoagulant drugsmay help reduce the risk of clot formation-beforeor after such a stroke. (In fact, almost all people withatrial fibrillation should be on some form of long-term aspirin or anticoagulant drug therapy. SeeChapter 23.)

The third form of stroke caused by blood clottingis called a lacunar infarction or lacunar stroke. Thesestrokes are the result of occlusion (complete block-

age) of arterioles, the very small ends of the arteriesthat penetrate deep into the brain, (See Figure 18.6.)The small size of the vessels sometimes makes lacunarstrokes difficult to diagnose; in addition, some haveno noticeable symptoms. There are, however, severalclassic syndromes that suggest the possibility of alacunar infarction. The most common is a pure motorstroke, in which damage is confined to the main ca-bling system for motor signals from the brain to thespinal cord (internal capsule). As a result, the patientdevelops one-sided weakness without other symp-toms. Similarly, a lacunar stroke in the thalamus (themain sensory relay center to the brain) can cause apure sensory stroke. Surgery and the use of anti-coagulant drugs do not appear to help a great dealin the short-term management of people with lacunardisease. Treatment concentrates on modification oflong-term risk.

In spite of the most aggressive workup availablein the 1990s, the mechanism of ischemic stroke re-mains unknown in over a third of all cases. Many ofthese cases of infarction of unknown cause appear tobe due to embolism. Refinements in imaging tech-nology and earlier evaluation of patients may helpcategorize these strokes better in the future.

At present, however, much can be determined bythe specific symptoms and signs that a patient man-ifests. Defining the mechanism of a stroke can helpdetermine prognosis, suggest appropriate therapy,and help the physician prepare the family for whatto expect. For example, patients with lacunar strokeoften recover their strength better than those whosuffer other types; thrombotic strokes tend to worsenduring the acute period before recovery begins; andembolic strokes are associated with a high rate ofrecurrence within the first few weeks. “

STROKE

the walls of these small arteries, and eventually they burst. The term “cerebral” (meaning related to the part of the brain called the cerebrum) is also used.

About two-thirds of patients with an intracerebral hemorrhage have a history of hypertension; diabetes and atherosclerosis accelerate the damage. Other causes of bleeding into the brain include brain tumor,trauma, arteriovenous malformation (AVM), and stimulant drugs such as amphetamines and cocaine.

Intracerebral hemorrhage accounts for about 10 to 15 percent of all strokes. The onset of symptoms is usually acute, with severe headaches and decreased consciousness. Other symptoms depend on the size and location of the hemorrhage. One type of brainhemorrhage, cerebellar hemorrhage, is especially im-portant to recognize because prompt evaluation,often followed by surgery, can be lifesaving. Cere-bella hemorrhage means bleeding into the cerebel-lum (rather than the cerebrum)—the part of the brainthat coordinates movement and balance. Its symp-toms usually include disequilibrium or dizziness,incoordination (especially trouble in walking), head-ache, nausea, and vomiting.

Treatment and prognosis of intracerebral hem-orrhage varies with the size and location of the hem-orrhage within the brain and the condition of thepatient. A hematoma (blood that has clotted) near thesurface may be easily evacuated (removed surgically),but deep bleeding may damage critical structureswithin the brain and pose a higher surgical risk.Whether surgery is performed or not, medical man-agement centers on respiratory care, blood pressuremanagement, and minimizing pressure within theskull. Seizures sometimes follow the hemorrhage, soanticonvulsant medications are often added to theregimen.

HEMORRHAGIC STROKES

Hemorrhage accounts for about 20 to 25 percent ofall strokes. In these strokes, blood seeps from a holein a blood vessel wall into either the brain itself (in-tracerebral hemorrhage) or the space around thebrain (subarachnoid hemorrhage).

BRAIN OR INTRACEREBRAL HEMORRHAGE

In this type of hemorrhagic stroke, blood leaks fromsmall vessels at the base of the brain. Long-term ex-posure to high blood pressure is thought to weaken

SUBARACHNOID HEMORRHAGE

Subarachnoid hemorrhage is usually caused by ananeurysm or a vascular malformation (described be-low). In addition to the damage caused by the bloodshooting out of the artery, damage can be furtherworsened by the mass of blood pushing up againstadjacent areas of the brain and blood vessels, orthrough secondary effects of the extruded blood onthe brain’s blood vessels (vasospasm).

The classic clinical feature of a subarachnoid hem-orrhage is the sudden onset of an excruciating head-ache. It is often associated with a stiff neck, changein consciousness, nausea and vomiting, diffuse intel-lectual impairment, and seizures. Other symptoms

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may occur, depending on the location and size of thehemorrhage.

Patients with symptoms suggestive of a subarach-noid hemorrhage should have a CT scan, which willindicate the presence of blood in about 80 percent ofcases. If the CT scan is negative or equivocal, a spinaltap (lumbar puncture) should be performed to lookfor evidence of bleeding.

ANEURYSMAn aneurysm is an outpouching in the wall of a bloodvessel that forms at a point where the wall is weak.Although the weakness may be present at birth, theaneurysm usually forms and grows later in life. Theoutpouching may go unnoticed for years, or may sud-denly rupture, in which case it can sometimes be fatal.The peak age range for an aneurysm rupture is be-tween 40 and 60 years old. Aneurysms sometimes runin families; some are associated with other diseases.About a quarter of patients with one aneurysm willhave additional ones.

The major impact of an aneurysm is the result ofthe rupture and bleeding, but the event may be fol-lowed in a few days by a secondary constriction ofblood vessels, known as vasospasm. The vasospasmmay be so severe that it impairs blood flow to thebrain and causes a secondary ischemic stroke. Someadvances have been made recently in treating vaso-spasm by using medications such as nimodipine (Ni-motop), increasing the blood volume (usually donewith intravenous fluids), or using medications to in-crease blood pressure.

An aneurysm can be treated surgically by placing aclamp at the base. The timing and type of surgery varieswith the size and location of the aneurysm, the extentof the bleeding, and the neurological status of the pa-tient. Under ideal circumstances, the surgery should beperformed within 48 hours after the hemorrhage. Thiseliminates the risk of rebleeding. Surgery attemptedfive to ten days after a subarachnoid hemorrhage maycause, or worsen, vasospasm.

Occasionally an aneurysm will be found before itruptures. It may be found because it is has pushedagainst important nerves or areas of the brain, caus-ing pain or other symptoms, or because clots formedin the pouch of the aneurysm have traveled down-stream and occluded a blood vessel, causing a TIAor stroke. Surgical clipping is usually recommendedfor unruptured aneurysms more than 10 mm (two-fifths of an inch) in diameter.

ARTERIOVENOUS MALFORMATIONAn arteriovenous malformation (AVM) is a tangle ofarteries and veins without the small vessels (capillar-ies) that normally connect the two. The walls of thevessels are often thin and have high rates of bloodflow, conditions that predispose to bleeding. AVMsmay produce symptoms by bleeding, putting pres-sure on structures within the brain, or shunting bloodaway from normal areas of the brain.

Small AVMs may not need to be treated, but whenthey are large or they cause significant symptoms,attempts should be made to obliterate them. This canbe done surgically, by using radiation, or with a rel-atively new radiologic technique that delivers smallpellets of glue that occlude the vessels leading to, andwithin, the AVM. Unfortunately many AVMs tend torecur.

Despite dramatic advances in our ability to diag-nose the causes of intracerebral hemorrhages, theresults of treatment remain disappointing. Mortalityremains high, and problems in those surviving areoften severe.

OTHER FORMS OF STROKE

In addition to the major causes of stroke describedabove, there are a number of other causes, includingthe two most common ones: cardiac arrest and he-matomas adjacent to the brain. In cardiac arrest, theheart stops pumping blood or does not pump effec-tively, and the brain is deprived of both oxygen andglucose. Although the entire brain is affected, certainareas are more vulnerable. Memory and coordinationare among the most frequent deficits after this typeof stroke.

Hematomas—accumulations of blood that are theresult of hemorrhage—sometimes occur in the out-ermost covering of the brain, the subdural or epidurallayers. These are usually caused by injury, but mayoccur spontaneously, especially in the elderly. In thistype of stroke, surgery can usually correct the prob-lem by removing the clot, and maybe lifesaving.

DIAGNOSING AND ASSESSINGS T R O K E

Anyone experiencing symptoms of a stroke requiresimmediate medical help. Even if the ultimate diag-

nosis is not stroke, many diseases that can mimic astroke are also medical emergencies.

If a physician cannot be contacted by telephone,the person should be taken to the nearest hospitalemergency department at once. Many types of strokerequire immediate treatment, and most of the prom-ising new therapies for stroke are effective only ifstarted within a few hours of the onset of symptoms.

A variety of diagnostic tools are available to thephysician, from history-taking and trained observa-tion to sophisticated radiologic imaging studies. Thetests performed will vary with the type of stroke, itsseverity, and the planned therapies. Regardless of thetests used, the goals are the same: to exclude non-vascular reasons for the neurological symptoms andto pinpoint the cause, location, and extent of thestroke.

HISTORY AND EXAMINATION

Perhaps the most important diagnostic tool is the in-itial history and physical examination of the patient.Critical details about the medical history may have tobe obtained from a family member if the patient isdisoriented or unable to speak.

During the examination, the physician will test avariety of neurological functions: orientation, mem-ory, emotional control, motor skills, tactile sensation,hearing, vision, and the ability to read, write, andspeak. Using knowledge of brain anatomy and func-tion, a neurologist can usually identify the area of thebrain that is damaged by noting the specific symp-toms. For example, difficulty with walking and bal-ance is likely due to damage to the cerebellum.Specific deficits on one side of the body point to dam-age in the opposite cerebral hemisphere.

The general examination should also include asearch for evidence of high blood pressure, coronaryheart disease, or disease in other parts of the vascularsystem. Using findings from the history, neurologicalexamination, and general examination, the physicianwill formulate an initial opinion about the locationand type of stroke. Laboratory and radiological testswill then be ordered to help confirm or exclude thephysician’s initial suspicions.

LABORATORY TESTS

Tests are usually done on samples of blood, urine,and, occasionally, cerebrospinal fluid (fluid aroundthe brain and spinal cord). They focus initially on ex-cluding conditions that can mimic or worsen a stroke,such as infection or low levels of blood sugar. Screen-

STROKE

ing may also be done for diabetes, elevated blood cholesterol, bleeding disorders, and abnormalities in blood proteins—risk factors for cardiac disease and recurrent stroke.

IMAGING STUDIES

Computed tomography (CT) scans and magnetic res- onance imaging (MRI) are techniques that produce anatomic pictures of the brain. Computed tomogra- phy scans use multiple X-rays and computer recon- struction to create cross-sectional images of internal structures. Magnetic resonance imaging uses mag-netic fields to create images. Each has advantages indifferent circumstances. Because these scans can de-lineate (and thus help exclude) such conditions as tu-mors, abscesses, and bleeding from trauma, they areoften done early after a stroke. They can usually dif-ferentiate ischemic strokes from those that are dueto bleeding.

The studies are often repeated several days afterthe onset of a stroke to determine its size and becausethe full extent of the damage may not be seen untilthen. If a patient’s condition worsens, the tests maybe repeated in order to help determine the cause ofthe deterioration.

Magnetic resonance devices are also capable ofspectroscopically (based on spectrums of light) mea-suring chemicals within the brain. These measure-ments may be important in determining themechanism of a stroke and the prognosis and besttherapy for a particular stroke victim.

CARDIAC EVALUATION

An electrocardiogram (ECG) is usually the first stepin a cardiac evaluation. An ultrasound examination(echocardiogram) of the heart may help pinpoint asource of an embolus.

ANGIOGRAPHY

Angiography involves the injection of a dye or con-trast medium into an artery in order to study theblood vessels via X-ray pictures. It can be used todetect many of the abnormalities that cause stroke,including narrowing or occlusion of a blood vessel,embolus, atherosclerosis, dissections, arteriovenousmalformations, and aneurysms.

Because angiography is an invasive technique, inthat it introduces instruments and substances into thebody, it may be associated with serious complica-

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tions. These include inducing or worsening a stroke,allergic reactions to the contrast medium, and, veryrarely, death.

Newer techniques using magnetic resonance im-aging can be used to produce an angiogram nonin-vasively. As these images continue to improve inquality, they may replace conventional angiography.

ULTRASOUND

Ultrasound is a noninvasive technique that usessound waves and their echoes to visualize structuresand blood flow within the body. Two types of ultra-sound are used in stroke diagnosis carotid ultra-sound (to measure flow in the carotid arteries) andtranscranial Doppler (to measure flow in the intra-cranial arteries). Although the anatomical informa-tion it produces is not as precise as that obtainedthrough angiography, ultrasound has the advantagesof being painless and risk-free. It is often used toscreen patients before invasive studies are done.

BLOOD-FLOW STUDIES

Blood-flow techniques-such as positron emissiontomography (PET), single-photon-emission com-puted tomography (SPECT), and xenon inhalation—provide information on blood flow in the brain. Thesetests may show changes immediately after the onsetof stroke symptoms, while computed tomography ormagnetic resonance imaging may remain negativefor several hours or days after a stroke.

The role of these tests is still being defined, andthey are generally available only in large medical cen-ters. They may be useful in determining the mecha-nism of a stroke (e.g., carotid stenosis) or determiningprognosis early in the hospitalization.

STROKE TREATMENT

The primary goals of stroke treatment have changed,thanks to new drug therapy. Doctors now attempt tohalt the progression of the stroke and to preventrecurrence. In years past, when it was believed thatall brain cells died after about four minutes withoutblood flow, stroke was considered to be largely un-treatable. Spurred on by observations in animals thatat least partial recovery can occur after even an hour

of complete ischemia (lack of oxygen), researchershave discovered that regions of the brain with veryminimal blood flow can survive-although they donot function normally-for several hours or perhapsdays. These viable cells surrounding an infarct, calledthe “ischemic penumbra," are the focus of numerousexperimental drug therapies aimed at restoring bloodflow or preserving cell function.

As researchers learn more about the mechanismsof stroke, they are realizing that it is not simply a lackof blood flow that causes death of tissue; a progres-sion of other processes (including inflammation andtoxic buildup), called the ischemic cascade, may playan even greater role in causing lasting necrologicdamage. Doctors believe that if they can interrupt thiscascade, they may be able to prevent the devastatingbrain damage that was once the inevitable conse-quence of stroke.

TREATMENT OF ACUTE STROKE

Most treatment of stroke during the acute phase cen-ters on maintaining fluids and electrolytes (chemicalsubstances in the blood, such as sodium and potas-sium), avoiding low blood pressure (hypotension),and avoiding the secondary complications of strokeand paralysis. The latter includes pneumonia, urinarytract infections, muscle contractures, and pressurebreakdown of the skin (bedsores). The physician willalso attempt to anticipate and avert deterioration af-ter a stroke. This will require constant monitoringand evaluation and may necessitate a number of lab-oratory tests.

Anticoagulant medications such as heparin aresometimes used to treat an acute ischemic stroke.While heparin does not dissolve existing clots, it canprevent the formation of new ones. Thus it may helpprevent subsequent strokes, which occur in up to 20percent of ischemic stroke cases.

Because heparin can increase some patients’ ten-dency to bleed, its use is often restricted to those withthe highest risk of recurrent stroke: patients with aprogressing stroke, more than one TIA, or a cardiacsource of embolism (often seen with myocardial in-farction, atrial fibrillation, or valvular diseases). Re-lated drugs known as heparinoids are now beingevaluated and appear to be at least as effective, witha lower risk of bleeding.

Surgery is usually not used to treat an acute stroke,although it maybe indicated for a hemorrhagic stroke(subarachnoid and brain hemorrhages) or a recentblockage of a carotid artery.

LONG-TERM TREATMENT OF TIA AND STROKE

After the acute phase of a TIA or stroke has passed,emphasis is placed not only on recovery and reha-bilitation but also on preventing further vascularevents, including ischemic stroke and myocardial in-farction. Therapy may include modification of riskfactors, drugs, or surgery, or a combination.

Risk factors are discussed earlier in this chapter.Treatment of high blood pressure and diabetes, alongwith smoking cessation, are probably the most im-portant. The effects on stroke risk of modifying otherfactors–controlling weight, lowering cholesterol,and moderating alcohol intake—are not as well stud-ied, but these modifications are generally recom-mended. Treatment of additional risk factors is bestconsidered on an individual basis in consultation witha physician,

ANTIPLATELET MEDICATIONS

Platelets are cell fragments that circulate in the bloodand play a key role in the formation of clots. Medi-cations that inhibit platelet function, such as aspirin,lessen the tendency of blood to clot. Patients at highrisk of stroke are known to benefit in several waysfrom taking aspirin daily. Aspirin therapy lowers therisk of stroke and stroke-related death.

Unfortunately, aspirin therapy is complicated bythe fact that the optimal dose is unknown. If the doseis too low, the aspirin will not have an effect on theplatelets; if it is too high, it may cause the blood vesselwalls to release chemicals, resulting in the formationof more clots. Most authorities recommend between325 and 1,200 mg aspirin per day (one to four tablets),a higher dose than that usually recommended to pre-vent a heart attack. More recent evidence suggeststhat doses as low as 80 mg per day may also have aprotective effect.

Although aspirin has been shown to reduce therisk of stroke, it may not’ be appropriate for all pa-tients, For example, it should not be used in patientswhose blood pressure is not normal. Before begin-ning any treatment, even as simple as aspirin therapy,a patient should consult his or her physician. Aspirinshould always be part of a larger program directedat all aspects of vascular disease prevention.

Ticlopidine, a relatively new antiplatelet medica-tion, appears to be about 15 percent more effectivethan aspirin in reducing the risk of stroke in peoplewho have had a TIA or minor stroke. This slight im-provement in efficacy must be weighed against moreserious side effects such as rash, diarrhea, and low-ered white cell counts, and higher cost.

ANTICOAGULANTS

Like antiplatelet medications, anticoagulant drugs also interfere with the clotting mechanism, in thiscase by affecting the action of enzymes necessary for clotting. A commonly used anticoagulant is warfarin (Coumadin). Because it is a more powerful drug than aspirin, it is usually recommended only when aspirin therapy has failed or when it is clear that the source of the clots is the heart (e.g., when the patient has atrial fibrillation or has had a myocardial infarction or valvular heart disease).

Patients taking warfarin must be carefully moni- tored via periodic blood tests, known as prothrombintime tests, that measure the speed of clotting. Withoutmonitoring, the dosage may be too low, increasingthe risk of stroke, or too high, increasing the risk ofbleeding complications. Patients also need to beaware that certain medications and foods (leafy greenvegetables such as spinach and other foods high inVitamin C) can alter the effectiveness of warfarin.However, dietary restrictions are not usually advisedfor patients on anticoagulants.

SURGERY

The goal in surgery is to provide a pathway for bloodto get to the brain. This is most commonly done usinga procedure known as carotid endarterectomy, inwhich a stenosis (narrowing) or ulceration of an ath-erosclerotic plaque in the carotid artery is removed.

Similar interim results were released in 1991 fromtwo large studies of carotid endarterectomy. Partic-ipants in the study had experienced either a recentTIA or a nondisabling stroke, and each had a carotid-artery blockage of more than 70 percent. Participantswho underwent endarterectomies showed a sixfoldreduction in strokes, compared to those who did nothave surgery. This dramatic result suggests that ca-rotid surgery is likely to play a key role in the pre-vention of recurrent stroke in the coming years.

There are, however, several important points thatshould be made in interpreting these results. First,the carotid narrowing must be in a particular portionof the artery. For example, if a patient has a smallstroke in the left brain hemisphere, this is not an in-dication for surgery on a narrowed right carotid ar-tery. Secondly, these studies were carried out atleading medical centers that have low complicationrates. Thus, the results suggest that carotid surgery,in the best of circumstances, reduces the risk ofstroke. Whether this will hold true for all hospitalsremains to be demonstrated. Finally, as physicians

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better understand stroke risk factors, it maybe pos-sible to use even more precise criteria to select pa-tients for surgery. For example, even considering thegroup of people with the most severe carotid nar-rowing, there are many who will not have a stroke.Using risk stratification models and blood flow mea-surements, it maybe possible to identify people whodo not require surgery, even though they may havea carotid-artery blockage of more than 90 percent.

Despite the encouraging results of these two stud-ies, there are still no answers for people with a carotidartery narrowing of less than 70 percent or for thosewho have not yet had a stroke or TIA. These questionsare being investigated actively in clinical studies, andresults should be available in the next few years.

Although conceptually appealing, the removal ofa carotid stenosis is not without risk: There is a 10percent complication rate across the United States.There is evidence to suggest that only medical centerswhere the complications and mortality rates are lessthan 6 percent should be performing the procedure.

Another way of providing blood to the brain is viaa procedure known as extracranial-intracranial by-pass, which involves connecting an artery from thescalp to one on the surface of the brain through asurgical opening in the skull. This procedure was re-cently tested in a large cooperative trial and was notdemonstrated to be beneficial; it is not recommendedat this time.

RECOVERY FROM A STROKE

Recovery after a stroke is dependent on many factors:the specific site of the brain injury, the general healthof the patient, his or her personality and will, familysupport, and the care received. The best recovery isusually seen in a patient who has had a small ischemicstroke. Large subarachnoid hemorrhages pose themost difficult challenge for recovery. Nevertheless,there are few solid rules for prognosis, and each caseshould be considered on an individual basis.

Caring for a patient after a stroke is a multifacetedand often complex process. The care must includehelping the patient recover from deficits (such asweakness of an arm or leg or an inability to speakclearly) and learn to function with any losses, dealingwith the patient's emotional issues and those of thefamily, and preventing recurrent strokes.

REHABILITATION

In the immediate poststroke period, medical person-nel care for the patient’s physical needs in order toreduce the risk of complications. Patients who havedifficulty swallowing, for example, may need to befed intravenously until they are able to swallow waterand food adequately. Most patients will be able to getout of bed for increasingly longer periods within twoto three days and be able to leave the hospital in tendays to two weeks.

Planning for rehabilitation should begin as soonafter the stroke as possible. Early attention to weaklimbs can greatly improve the chances of a successfulrecovery. Simple measures such as frequent positionchanges while in bed and exercise of the paralyzedareas (including moving the arms and legs by phys-ical therapists, nurses, and family members) can im-prove the circulation, maintain joint flexibility,maintain normal muscle tone, and get the family andpatient involved in the recovery process. Physicaltherapy generally starts within four or five days afterthe stroke.

The rehabilitation process becomes more active asthe patient becomes medically stable (usually withina day or two). Passive range-of-motion exercises, inwhich a family member, nurse, or physical therapistperforms most of the movement, are replaced by ac-tive range-of-motion routines, in which the patientstrives to regain strength in the affected limbs.

The efforts of the rehabilitation team also mustfocus on the mental aspects of recovery-not only tohelp patients overcome deficits in knowledge ormemory, but also to help prepare them for the longrecovery process and encourage them to lead livesas full as possible with the abilities they retain. It isimportant to keep in mind that many people havefought their way back from a stroke and continuedto lead useful and fulfilling lives. Patients with theability to make decisions should be included in familydecision-making.

No program can succeed without a strong desireby the patient to be independent. Nevertheless, familyinvolvement is also a key ingredient in a successfulrehabilitation program. The family can provide a pos-itive environment for the patient, nurturing the desireto be independent while reassuring the patient thathe or she is still wanted, needed, and loved. Oftengiving a patient something to do, and to live for, ishalf the battle.

The family is also important because althoughmost patients are able to leave rehabilitation facilitiesto return to their families, often they continue to have

Possible Consequences ofLeft- and Right-Brain InjuryDamage to the left side of the brain

Right-side paralysisSpeech and Ianguage deficitsSlow, cautious behaviorMemory problems related to languageRight-side neglect (less common than left-side;

see below)

Damage to the right side of the brainLeft-side paralysisSpatial-perceptual problemsLeft-side neglectQuick, impulsive behaviorMemory problems related to performance

some problems and their recovery process must con-tinue at home. Family members should take as muchof the responsibility for physical therapy at home asis practical. A nurse or physical therapist visiting thehome for a few hours a week cannot alone providethe sustained encouragement and the level of activityneeded to facilitate recovery.

Beyond the patient and family, rehabilitation is ateam effort with input from physiatrists (rehabilita-tion physicians), neurologists, nurses, physical ther-apists, occupational therapists, speech therapists,and social workers. Their common goal is to help thepatient and family achieve the maximal level of func-tioning possible.

Most stroke patients will need several types oftherapy, described below, but the mix and amount ofeach will be tailored to the patient’s needs and symp-toms. Although symptoms of brain damage varywidely, some generalizations can be made. A com-mon way of characterizing stroke injury is by the sideof the brain affected. An injury to the right side ofthe brain that results in paralysis—temporary orpermanent—will affect the left side of the body. Con-versely, right-sided paralysis is the result of injury tothe left side of the brain. Certain language problemsand changes in behavior are also associated with left-or right-side damage. (See box, “Possible Conse-quences of Left- and Right-Brain Injury.”)

PHYSICAL THERAPYThe primary objective of physical therapy is to helppatients who are partially paralyzed learn to walkagain. Starting slowly, the therapist will first work

with the patient on simple exercises to increase range of motion and muscle tone. Once the patient is able to turn over and sit up unsupported, the therapistusually will have the patient try to start walking. A patient learns to walk while holding on to a bar for support, and then with the aid of a quadruped cane (one with a sturdy four-footed base) and, usually, an- kle-foot braces for stability. An estimated 75 percent of all stroke survivors are eventually able to walk in- dependently and will regain most of their ability by the end of the first month.

OCCUPATIONAL THERAPYAlthough the ultimate goal is to help the patient re-sume some sort of employment, if possible, occupa-tional therapy encompasses all aspects of everydaylife. Occupational therapists help patients regain themuscular coordination necessary to perform basicactivities such as dressing, bathing, and using thetoilet. A patient who is paralyzed on one side is taughthow to maneuver clothing using the able side of thebody, and is advised about clothing styles-such aspullover rather than buttoned shirts-that are easiestto maneuver. Patients are taught how to use a wheel-chair, and how to transfer from bed to wheelchairand vice versa. The occupational therapist will alsoadvise the family about changes that can make a pa-tient’s move back home easier and safer: handrails inthe bathtub and by the toilet, a raised toilet seat, andramps in place of stairs, and widened doorways toaccommodate a wheelchair, if one is still necessary.

SPEECH THERAPYTwo disorders that may occur after a stroke areaphasia (difficulty with language) and dysarthria (dif-ficulty with articulation). Aphasia and dysarthria arenot necessarily associated with a loss of the ability tothink or understand.

Dysarthria is caused by weakness or paralysis ofmuscles in the face, mouth, neck, or throat. It canresult in slow, labored speech, slurring of words, ora change in voice quality. Often the paralysis of theface muscles causes drooping of one side of the faceand perhaps drooling.

Most stroke patients with left-brain injury havesome degree of aphasia. It manifests itself in differentways in different patients; there may be difficultymaking oneself understood, comprehending others’words, or reading, writing, or doing arithmetic. Thecomplexity of the problem mirrors the complexity of

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the communication process, which involves on theone hand organizing thought, finding the words toexpress it, and producing the words, and on the otherhand perceiving that someone wants to say some-thing to you, following the words as they are spoken,and then comprehending the message in its entirety.

Aphasia may be equally frustrating for the patientand the family and friends, who may feel they can nolonger communicate with the patient. Imagine wak-ing up into a world where you mean to say one thingand something completely different comes out ofyour mouth, or one where your family seems to bespeaking a foreign language that you cannot com-prehend. This is what an aphasic patient may expe-rience. But with the help of a speech therapist and acooperative family, a stroke survivor has an excellentchance of regaining communication skills. If the pa-tient is not able to produce speech specifically, thatdoes not mean he or she cannot use and comprehendlanguage in the larger sense of the word, which en-compasses other communication tools such as ges-tures, movements, facial expressions, and noises.

A speech therapist should lay the groundworkwhile the patient is in the hospital, first working toobtain from the patient reliable (verbal or nonverbal)yes or no responses to questions. Then the therapistuses a variety of techniques, including repetition andpointing to pictures, to reestablish the fundamentalsof language. In most cases, the knowledge of lan-guage hasn’t been eradicated, and patients just needto regain their ability to recall what they have learnedin the past. As with other memory losses, the patientwill often regain ability to remember events that hap-pened in the distant past, but will not be as able toremember things that happened in the very recentpast—where he or she left a hat ten minutes ago.

ADJUSTING AFTER A STROKE

Rehabilitation may continue on an outpatient basisafter the patient has returned home, and recoverymay continue for months or even years. The mostdramatic changes occur in the first three to sixmonths or so; smaller changes may continue for longafterward.

There are no clear guidelines for how much activ-ity benefits stroke patients and how hard to pushthem. They should be pushed hard enough to be chal-lenged, but not so hard as to be continually frustrated.

Recovery from a stroke can be a painfully slow pro-cess. Both family and patient should take time to notesuccessful efforts, and family members need to offerpositive feedback, encouragement, and praise.

The stroke does not just happen to the patient-ithappens to the family as well. Understanding howstrokes can affect patients will make it easier for fam-ilies to deal with the recovery process. Some of themajor behavioral, cognitive, and emotional effectsare discussed below.

APHASIAThe lack of ability to communicate may sometimesimprove rapidly—within a few days or a week—butin many cases, recovery is a long process. The re-covering aphasic patient needs stimulating and un-derstanding companionship. In addition to helpingthese people feel loved and supported, engagingthem in conversation and activity reinforces languageskills. A patient who is left alone with little to do willprogress much more slowly than one who is madeto feel a part of the family, or has simple, arousingthings to do, such as looking through a picturemagazine.

Just as parents can grasp what toddlers meanwhen they gurgle or grunt or use made-up words,family members can often learn to understand thepatient’s limited, disjointed, or inappropriate speechduring the first few weeks after the stroke. Patientsmay say “car” when they mean “couch,” and maynot realize that they are not being understood. Theymay use swear words that they never uttered beforethe stroke, or repeat the same word over and over.Family and friends can learn to speak slowly, usesimple words and short sentences, and repeat themif necessary. A variety of computer software designedto help in language retraining is now available,

It is important for the family and friends neitherto overestimate nor underestimate what the recover-ing patient understands. If the patient says yes orsmiles and nods in agreement with something that issaid, he or she may be responding to the speaker’sfacial expression or expressing pleasure about beingspoken to. A speaker who consistently overestimateswhat the patient understands will become annoyedthat the patient doesn’t follow through and may de-cide that the patient is forgetful or uncooperative. Orthe speaker may talk too much, thus overloading thepatient and interfering with any understanding thepatient may have. Unrealistically high expectationsabout what the patient should be able to do can be

STROKE

very frustrating for both patient and family. On the tious, and disorganized when faced with an unfa-other hand, if the patient's cues that he or she doesunderstand are missed, family members are less likelyto continue to engage the patient in communication,which can have devastating effects on emotions andrecovery. To avoid either extreme, family membersneed to be sensitive to nonverbal cues as well as ver-bal responses and to test understanding occasionallyby saying something improbable and noting the pa-tient’s response. (See box, “Tips on Communicatingwith Stroke Survivors.”)

OTHER NECROLOGIC DEFICITS

Family members can also help lessen the impact ofother necrologic-behavioral changes. If patients havedifficulty remembering recent events, it is importantto remind them of their recent successes in regainingfunctions. Patients with left-brain damage (with orwithout right-sided paralysis) are often slow, cau-

miliar situation-even if their behavioral style wasquite different before the stroke. Family members canhelp the patient by giving positive feedback for thingsdone correctly. Patients with right-brain damage, onthe other hand, tend to act impulsively and hastily;they are often poor judges of their own abilities andsafety. Family members can help by reminding pa-tients to take things slowly and carefully.

Some stroke patients suffer a loss of half of theirvisual field in each eye. Some patients, particularlythose with right-brain damage, also have one-sidedneglect: they do not compensate for their visual lossby turning their heads. Rather, they ignore every-thing—including objects and even sensations—onthe side of the body where vision is impaired. Oftena patient will not even recognize an arm or leg asbeing part of his body. People may have to approachpatients from their unimpaired side in order to benoticed. Putting objects on the patient’s good side—

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such as clothes only on one side of the closet—canmake management easier.

Deficits in spatial relations-judging the size, po-sition, distance, or speed of objects, for example—are common among people with right-brain damage.This can create problems for self-care, making it dif-ficult for a person to button a blouse correctly, steera wheelchair without bumping into obstacles, read anewspaper without losing his or her place, or evensip soup from a spoon.

Other common, but not universal, problems thatmay occur following a stroke include:

Poor concentration

Poor judgment of time

Disturbed sleep cycles

Impaired memory

Impaired judgment

Loss of sexual desire

Poor emotional control

Depression

EMOTIONAL IMPAIRMENTOften families and patient focus on the physical im-pairments after a stroke. These are readily apparentand easily understood. But the brain is also respon-sible for our thoughts and emotions. It is this aspectof damage after a stroke that is often the most difficultto deal with.

People who have recently suffered a stroke mayhave a loss of emotional control because of damagein the area of the brain that controls emotions. As aresult, they may cry or laugh suddenly, often inap-propriately, at times when they do not feel especiallysad or happy. Some patients may become irritatedand express anger with little provocation. Simply dis-tracting the patient can often interrupt the emotionalbehavior.

On the other hand, true depression is not uncom-mon in stroke patients, whose lives have beenchanged drastically and who feel discouraged orhopeless. In part this can be a natural reaction to adevastating disease and the often slow and difficultrecovery process. Often it is also caused by damageto areas of the brain and by neurochemicals respon-sible for mood and motivation. Signs of depressioninclude excessive crying (which cannot be easily in-terrupted], fatigue, sleep and eating disorders, andloss of interest in activities. Support from family

members and an emphasis on the positive progressthat has been made—without ignoring the existenceof deficits-can be helpful. Antidepressant medica-tions can be prescribed for patients whose down-heartedness is hampering their progress.

Problems such as sexual dysfunction, loss of self--esteem, and difficulties in family relationships arebest dealt with openly and with the help of trainedmedical personnel. These are important issues forquality of life following a stroke and should not beignored. The important thing to remember is thatmany of these conditions can be helped. Sometimesjust the knowledge that this is a common problemand that it is often self-limited is enough to get thepatient and family back on track. In more seriouscases, therapy (personal or family) and medicationsmay be necessary. The key is to speak frankly andkeep the physician and other health care personnelinformed.

PHYSICAL ACCOMMODATIONSPlanning for returning home after a stroke may re-quire some physical adjustments in the house. Manyof these are simple and can be done by the family(rubber shower mats, soap enclosed in a cloth pouchto avoid slipping, handgrips, and removal of smallscatter rugs); others may require more detailed plan-ning and construction (ramps, lowered counters,high toilets, changing the height and location of lightswitches). Useful devices such as one-handed cardholders, rocker knives, nonskid mixing bowls, andmodified telephones can be purchased, often throughspecialized catalogs. These modifications are bestplanned in conjunction with occupational therapistsand by sharing experience with other familiesthrough local support groups, such as stroke clubs.

TOWARD THE FUTURE

Several exciting approaches to stroke therapy are un-der investigation. All are in, or near, clinical testingin humans.

One investigational approach is thrombclytictherapy—the use of drugs such as t-PA {tissue plas-minogen activator) to dissolve a clot and reopen theoccluded vessel causing the stroke. This therapy hasalready proved successful in treating heart attacks

and shows promising early results in stroke patients.The major drawback is an increased risk of bleeding.

Another approach is to route blood flow aroundthe occlusion through small collateral vessels, aftermaking these vessels larger by, for example, usingvasodilating agents such as calcium channel blockers.An alternative is to lower the viscosity (thickness) ofthe blood (by, for example, adding plasma expanders)in order to make the flow through the small vesselseasier.

Researchers are also attempting to determine thechemical reactions that lead to permanent damageduring a stroke. Once these are understood, itmay be possible to inhibit these harmful reactionsselectively and lessen the damage. Calcium-channel-blocking drugs, already being used to treat other car-diovascular conditions, may help reduce the damagecaused by a stroke.

Other drugs being investigated also work to pro-tect the nerve cells. These include the NMDA-recep-tor blockers.

One of the newest areas of investigation is resto-rative neurology, which studies how the brain andnerves repair themselves after injury. Current med-ical wisdom says that in adults, nerve cells do notdivide in order to create new cells, so that damagedbrain cells cannot be replaced. This maybe only par-tially true. While cell regrowth is not yet possible, itmay be possible to influence how neurons commu-nicate with each other after injury.

STROKE

Nerve cells are “connected” to thousands of other nerve cells through connections called synapses, which change after injury to the brain. It appears that gangliosides, a class of molecules on the surface of neurons, help new synapses form. By giving strokepatients extra amounts of gangliosides, it may be pos- sible to increase the number of synapses, permitting the brain to develop a wider variety of compensatory brain circuits and minimize the deficits. This therapy, now in clinical trials, would not change the size of the stroke, but could improve outcome for the patient.

SUMMARY

Neurology is on the verge of major breakthroughs instroke treatment that hold promise for being able todrastically reduce the effects of stroke. But despiteadvances in treatment, prevention remains the mosteffective way of decreasing the national burdencaused by strokes. Patients at risk must work withtheir doctors to reduce their likelihood of falling vic-tim to a disabling stroke. Life-style changes and bettermanagement of high blood pressure have alreadybeen responsible, along with better treatment ofstrokes when they do occur, for a more than 50 per-cent decrease in stroke deaths over the past 20 years.

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