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VASCULAR SV$lR.1 AND HE....\1ATOLOGY

391

arteries

Abdomi al

aorta

Iliac

arteries

A

B

c

Figure 6-2. A. Fusiform aneurysm of the aorta. B. ConsequeNces of dissection from the ascending aorta across the arch of the aorta. C. Saccular aneurysm of the descendmg aorta. (With permission from BL Bullock led).

Pathophysiology: Adaptations and Alterations in Function {4th ed}. Philadelphia, Lippillcott-Ravell, 1996;532.)

392 AClJTE CARE HANDBOOK FOR I'HYSICAL THERAPISTS

Arterial Thrombosis

Arterial thrombosis occurs in areas of low or stagnant blood flow,

such as atherosclerotic or aneurysmal areas. The reduced or turbulent

blood flow in these areas leads to platelet adhesion and aggregation,

which then activates the coagulation cycle to form a mature thrombus

(clot). Blood flow may then be impeded, potentially leading to tissue

ischemia with subsquent clinical manifestations,21 ,23

Arterial Emboli

Arterial emboli arise from areas of stagnant or disturbed blood flow

in the heart or aorta. Conditions that predispose a person to emboli

formation are (1) atrial fibrillation, (2) myocardial infarction, (3) infective endocarditis, (4) cardiac valve replacement (if not properly anticoagulated), (5) chronic congestive heart failute, and (6) aortic atherosclerosis. Areas in which arterial emboli tend to lodge and

interrupt blood flow are arterial bifurcations and areas narrowed by

atherosclerosis (especially in the cerebral, mesenteric, renal, and coronary arteries). Signs and symptoms of thrombi, emboli, or both depend on the size of the occlusion, the organ distal to the clor, and

the collateral circulation available."

Treatment of thrombi, emboli, or both includes anticoagulation

with or withom surgical resection of the atherosclerotic area that is

predisposing rhe formarion of rhrombi, emboli, or both. Medical

management of arterial thrombosis can also include anti thrombotic

drugs (e.g., tissue factor or factor Xa inhibitors) or combined antithrombotic therapy with aspirin, and thienopyridine and warfarin, or both."

Hypertension

Hypertension is an elevated arterial blood pressure, both systolic and

diastolic, that is abnormally sustained at rest. Table 6- J 2 outlines

normal and hypertensive blood pressures for a given age group. Signs

and symptoms that can result from hypertension and its effects on

target organs are described in Table 6-13. Two general forms of

hypertension exist: essential and secondary.

Essential, or idiopathic, hypertension is an elevation in blood pressure that results without a specific medical cause bllf is related to the following risk factors"·25:

•

Genetic predisposition

• Smoking

VASCULAR SYSTEM AND HEMATOLOGY

393

Table 6-12. Hyperrension as It Relates ro Differenr Age Groups

Normal Blood Pressure

Hyperrensive Blood Pressure

Age

(SystolicIDiastolic)

(SystolicIDiastolic)

Infanrs

80/40

90/60

Children

100/60

120/80

Teenagers (age 12-

115/70

130180

17 yrs)

Adults

2�5 yrs

120-125/75-80

135/90

45-60 yrs

135-145185

140-160190-95

Older than 65 yrs

150/85

160/90

Source: Data from B Bullock. Pathophysiology: Adaptations and Alterations in Function (4th cd). Philadelphia: Lippincott-Raven, 1996;517.

• Sedentary lifestyle

• Type A personality

• Obesity

•

Diabetes mellitus

• Dier high in fat, cholesterol, and sodium

• Atherosclerosis

• Imbalance of vasomediator production, nitric oxide (vasodilaror), and endothelin (parent vasoconstricror)

Secondary hypertension results fr0111 a known medical cause,

such as renal disease and others listed in Table 6-14. If the causative

factors are treared sufficiently, systolic blood pressure may return to

normal limits.21

Management of hypertension consists of behavioral (e.g., diet,

smoking cessation, activity modification) and pharmacologic intervention to maintain blood pressure within acceptable parameters.

The primary medications used are diuretics and angiotensin-converting enzyme inhibirors along with beta blockers, calcium channel blockers, and vasodilarors.21,26-28 A summary of these medications,

their actions, and their side effecrs can be found in Appendix Tables

IV-I?, IV-2, IV-12, IV-14, and IV-3D, respectively.

394 ACUTE CARE HANDBOOK FOR PHYSICAL TIn· RAPISTS

Table 6-13. Hyperrensive Effecrs on Target Organs

Organ

Hypertensive Effect

Clinical Manifesrations

Brain

Cerebrovascular

Area of brain involved dictates presenaccident

tarion. May include severe occipital

headache, paralysis, speech and

swallowing disrurbances, or coma.

Encephalopathy

Rapid development of confusion, agitation, convulsions, and death.

Eyes

Blurred or impaired

Nicking (compression) of retinal artervision

ies and veins, ar rhe point of their

juncrion.

Encephalopathy

Hemorrhages and exudates on visual

examination.

Papilledema.

Heart

Myocardial infarction

Electrocardiographic changes.

Enzyme elevations.

Congestive heart failure

Decreased card inc output.

Auscultation of S3 or gallop.

Cardiomegaly on radiograph.

Myocardial hypertrophy Increased angina frequency.

ST- and T-wave changes on elecrrocar-

diogram.

Dysrhythmi,.

Ventricular or conduction defecrs.

Kidneys

Renal insufficiency

Nocturia.

Protcinuria.

Elevated blood urea nitrogen and crea-

tinine Icvels.

Renal failure

Fluid overload.

Accumularion of merabolires.

Merabolic acidosis.

Source: Data from B Bullock (cd). ))arhophysiology: Adapt;tl1ons and Alterations in

Function (4th cd). Philadelphia: Lippincott-Raven, 1996;522.

Clinical Tip

• Knowledge of medication schedule may facilitate activity tolerance by having optimal blood pressures at rest and

with activity.