1 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Chapter 42 CARDIAC GLYCOSIDES, ANTIANGINALS, AND ANTIDYSRHYTHMICS

2 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Heart Failure  Heart failure  Pathophysiology Preload Afterload  Right-sided Blood backs up in periphery  Left-sided Blood backs up in lungs

3 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Stages Characteristics 1 High risk for HF without symptoms or structural disease 2Some levels of cardiac changes (e.g., decrease ejection fraction without symptoms of heart failure) 3Structural heart disease with symptoms of HF (e.g., fatigue, SOB, edema, decreased physical activity) 4 Severe structural heart disease and marked symptoms of HF at rest ACC/AHA Stages of Heart Failure

4 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Heart Failure  Nonpharmacologic treatment  Limit salt intake.  Limit or avoid alcohol intake.  Stop smoking.  Decrease saturated fat intake.  Perform mild exercise as possible.  Laboratory tests  Atrial natriuretic peptide (ANP)  Brain natriuretic peptide (BNP)

5 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Cardiac Glycosides  Actions  Positive inotropic Increases myocardial contractility  Negative chronotropic Decreases heart rate  Negative dromotropic Decreases conduction  Increase stroke volume Increases cardiac output

6 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Cardiac Glycosides (cont’d)  Digoxin  Drug interactions Diuretics Glucocorticoids Antacids Herbal interactions  Digitalis toxicity  Anorexia, diarrhea, nausea, vomiting  Bradycardia, dysrhythmias, visual disturbances  Therapeutic level is 0.5 to 2.0 ng/mL  Antidote for digitalis toxicity  Inotropic agents

7 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Nursing Process: Digoxin  Assessment  Nursing diagnoses  Planning  Nursing interventions  Client teaching  Evaluation

8 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Other Agents Used to Treat Heart Failure  Angiotensin-concerting enzyme (ACE) inhibitors  Angiotensin II receptor blockers (ARBs)  Diuretics  Certain beta blockers  Carvedilol (Coreg)  Metoprolol (Toprol-XL)  Atrial natriuretic peptide hormone  Nesiritide (Natrecor)  Vasodilators

9 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antianginal Drugs  Types of anginal pectoris with treatment

10 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antianginal Drugs (cont’d)  Nonpharmacologic measures  Types of antianginals  Nitrates Side effects: headache, hypotension, dizziness, reflex tachycardia  Beta-adrenergic blockers  Nonselective and selective beta blockers  Calcium channel blockers  Side effects/adverse reactions

11 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antianginal Drugs (cont’d)  Beta-blockers  Atenolol (Tenormin), metoprolol (Lopressor), nadolol (Corgard), propranolol HCl (Inderal)  Action Heart rate and myocardial contractility are decreased, reducing oxygen need and anginal pain  Side effects/adverse reactions Bradycardia, hypotension Bronchospasm Depression Sexual dysfunction

12 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antianginal Drugs (cont’d)  Calcium channel blockers  Amlodipine (Norvasc)  Diltiazem HCl (Cardizem)  Felodipine (Plendil)  Nicardipine HCl (Cardene)  Nifedipine (Procardia)  Verapamil HCl (Calan, Isoptin)  Side effects/adverse reactions  Headache, dizziness, flushing  Hypotension, reflex tachycardia

13 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antidysrhythmic Drugs  Dysrhythmia vs. arrhythmia  Cardiac action potentials  Phase 0 to phase 4

14 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antidysrhythmic Drugs (cont’d)  Mechanism of drug action  Class I  Sodium channel blockers 1A: slow conduction, prolongs repolarization 1B: slow conduction, shortens repolarization 1C: prolonged conduction with little/no effect on repolarization  Class II  Beta-adrenergic blockers

15 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Antidysrhythmic Drugs (cont’d)  Class III  Prolong repolarization  Class IV  Calcium channel blockers  Others  Phenytoin, digoxin, ibutilide fumarate

16 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Practice Question #1 A client has angina pectoris. The client’s BP is 100/60. The nurse’s most realistic expectation when giving this client nitroglycerin 0.4 mg sublingual (SL) tablet for the anginal pain is A. an increase in BP. B. a decrease in BP. C. no effect on BP. D. a decrease of angina without any significant side effects.

17 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Practice Question #1 (cont’d) Answer: B Rationale: A side effect of nitroglycerin is hypotension owing to the vasodilation of blood vessels.

18 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Practice Question #2 A nurse is administering digoxin, mg, to a client. The nurse realizes nursing interventions for digoxin include (Select all that apply.) A. Checking the apical pulse rate before administration. B. Monitoring the client’s serum digoxin level. C. Instructing client to report pulse rate less than 60. D. Advising client to avoid foods high in potassium. E. Always giving an antacid with digoxin to reduce GI distress.

19 Copyright © 2012, 2009, 2006, 2003 by Saunders, an imprint of Elsevier Inc. Practice Question #2 (cont’d) Answer: A, B, C Rationale: The apical pulse should be taken before digoxin administration and the drug withheld if the heart rate is less than 60. The client’s serum digoxin level should be monitored and withheld if in toxic range. Therapeutic level is 0.5 to 2 ng/mL. Client should be advised to eat foods high in potassium. Client should be advised to avoid taking antacids with digoxin because they decrease absorption.