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long period of convalescence both before and after surgery, rendering them deconditioned. In general, heart transplant patients are immunosuppressed and are without neurologic input to their

heart. These patients rely first on the Frank-Starling mechanism to

augment SV and then on the catecholamine response to augment

both H R and SV. The reader is referred to Chapter 12 for information on heart and heart-lung transplantation.

Cardiac Medications

Cardiac medications are classified according to functional indications, drug classes, and mechanism of aerion. Cardiac drug classes are occasionally indicated for more rhan one clinical diagnosis.

CARDIAC SYSTEM

59

The primary functional indications and descriptions are provided

below. Appendix IV lists the functional indications, mechanisms of

action, side effects, and the generic (trade names) of these cardiac

medications.

Anti-Ischemic Medications

Anti-ischemic drugs attempt ro re-establish the balance between myocardial oxygen supply and demand.' To balance the supply and demand, medications can decrease HR or systemic BP or increase

arrerial lumen size by decreasing spasm or thrombus.

Medications that are successfully used for this task include the

followingSo:

• Beta-blockers (see Appendix Table lV- 1 2 )

• Calcium channel blockers (see Appendix Table lV- 1 4)

• Nitrates (smooth muscle cell selective) (see Appendix Table lV-24)

• Thrombolytic agents (see Appendix Table lV-29)

• Antiplatelet and anticoagulation agents (see Appendix Tables

IV- l O and IV-4, respectively)

Medications for Congestive Heart Failure

Heart failure treatment may include oral medications for a low-level

chronic condition or intravenous medications for an acute and lifethreatening condition. Medical management generally attempts ro improve the pumping capability of the heart by reducing preload,

increasing contractility, reducing afterload, or a combination of these.

Medication classes successful in achieving these goals include the

foliowingSo:

• Diuretics (see Appendix Table lV- l 7)

• Positive inotropes (see Appendix Table lV-27.A,B)

• Vasodilarors (sec Appendix Table IV-30)

• Angiotensin-converting enzyme inhibirors (see Appendix Table lV-2)

Notc: Digitalis toxicity can occur in patients taking digitalis as a positive inotrope. Refer ro Table 1 -20 for signs and symptoms of digitalis roxicity (digitalis level >2).

60

ACUTE CARE HANDBOOK FOR PHYSICAL THERAPISTS

Table 1-20. Signs and Symptoms of Digitalis Toxicity

System Affecred

Effecrs

Central nervous

Drowsiness, fatigue, confusion, visual disrurbances

system

Cardiac system

Premature atrial and/or ventricular conrracrions, paroxys-

mal supravenrricular tachycardia, ventricular tachycardia, high degrees of atrioventricular block, venrricular

fibrillarion

Gastrointestinal

Nausea, vomiting, diarrhea

system

Source: Data from SL Woods, ES Sivarajian-Froelichcr, S Underhill-Moner (cds). Cardiac Nursing (4th cd). Philadelphia: Lippincott, 2000.

Anriarrhythmic Drugs

Antiarrhythmic drugs attempt to normalize conduction of the cardiac

elecrrical sysrem .'o These drugs are classified in rhe following manner

according to their mechanism of action:

• Class [ (sodium channel blockers) (see Appendix Table IV-3)

• Class II (bera-blockers) (see Appendix Tables IV-3 and IV-l3)

• Class III (refracrory period alterations) (see Appendix Table lV-3)

• Class IV (calcium channel blockers) (see Appendix Tables IV-3

and IV-lA)

Antihypertensive Drugs

Antihypertensive drugs attempt to assist the body in maintenance of

normotension by decreasing blood volume, dilating blood vessels,

preventing constriction of blood vessels, preventing the retention of

sodium, or a combination of these.

Medication classes successful in achieving these goals include

the foliowingSo:

• Diuretics (see Appendix Table IV- I ?)

•

Beta-blockers (see Appendix Table IV- 1 2)

• Alpha-blockers (see Appendix Table lV- 'J 2)

• Calcium channel blockers (see Appendix Table IV- J 4)

CARDIAC SYSTEM

6 1

• AngiOlensin-converting enzyme inhibitors (see Appendix Table lV-2)

• Vasodilators (see Appendix Table lV-30)

Lipid-Lowering Drugs

Lipid-lowering drugs attempt to decrease lipid levels. They are usually

prescribed in combination with a change in diet and exercise habits

(see Appendix Table lV_22).5o Medications successful in lowering

lipid levels are the following:

• Anion exchange resin

• Fibric acid derivatives

• Hepatic 3-methylglutaryl coenzyme A reductase inhibitor

• Nicotinic acid

• Probucol

•

Fish oils

Physical Therapy Intervention

In the acute care setting, physical therapy intervention is indicated for

patients with cardiac impairments that result from CHF, Ml, or status

post CABG. However, a great majority of patients who receive physical

therapy present with one or many other cardiac impairments or diagnoses. Given the high prevalence of cardiac disease in the elderly population and the hospital admissions for the elderly, the likelihood of working with a patient who has cardiac impairment is very high. This

section discusses basic treatment guidelines for physical therapists

working with patients who have present or past cardiac impairments.

Coals

The primary goals in treating patients with primary or secondary cardiac pathology are the following'''

• Assess hemodynamic response in conjunction with medical or surgical management during self-care activities and functional mobility

• Maximize activity tolerance

62

ACtrrE CARE HANDBOOK FOR I'HYSICAL THERAI'ISTS

• Provide patient and family education regarding behavior modification and risk factor reduction (especially in patients with CAD, status post MI, PTCA, CABG, or cardiac transplant).

Basic Concepts for the Treatment of Patiellts

with Cardiac Dysftmcti01t

The patient'S medical or surgical status must be considered in intervention planning, because it is inappropriate to treat an unstable patient.

An unstable patient is a patient who clearly requires medical intervention to stabilize a life-threatening condition. A patient's status may flucruare on a daily or hourly basis. Table 1-2 1 provides general guidelines of when to withhold physical therapy (i.e., instances in which further

medical care should precede physical therapy).5o These are provided as

absolute and relative indications of instability. Relative indications of

instability should be considered on a case-by-case basis.

Once it is determined that a patient is stable at rest, the physical

therapist is able ro proceed with activity or an exercise program, or

both. Figure 1 - 1 0 provides a general guide to determining whether a

patient'S response to activity is stable or unstable.

Everything the physical therapist asks a patient to do is an activity

that requires energy and therefore needs to be supported by the cardiac system. Although an activity can be thought of in terms of absolute energy requirements (i.e., metabolic equivalents-refer to Table 1 - 1 2), an individual's response ro that activity is relative ro that individual's capacity. Therefore, although MET levels can be used to help guide the progression of activity, the physical therapist must be aware

that even the lowest MET levels may represent near-maximal exertion