Pharmacology, Chapter 48: Drugs for Heart Failure

A patient is recovering from a myocardial infarction but does not have symptoms of heart failure. The nurse will expect to teach this patient about: a. ACE inhibitors and beta blockers. b. biventricular pacemakers. c. dietary supplements and exercise. d. diuretics and digoxin.

a. ACE inhibitors and beta blockers. This patient is classified as having Stage B heart failure with no current symptoms but with structural heart disease strongly associated with the development of heart failure. Treatment at this stage includes an ACE inhibitor and a beta blocker to help prevent the progression of symptoms. Biventricular pacemakers are used for patients in Stage C heart failure and have more advanced structural disease and symptoms. Dietary supplements and exercise have not been proven to prevent structural heart disease. Diuretics and digoxin are used for patients with Stage C heart failure.

An 88-year-old patient with heart failure has progressed to Stage D and is hospitalized for the third time in a month. The nurse will expect to discuss which topic with the patient's family? a. Antidysrhythmic medications b. End-of-life care c. Heart transplantation d. Implantable mechanical assist devices

b. End-of-life care Patients in Stage D heart failure have advanced structural heart disease. For eligible patients, the best long-term solution is heart transplantation, but this patient probably is not eligible, given his advanced age. End-of-life care should be discussed. Antidysrhythmic medications are not indicated and may make symptoms worse. An implantable mechanical assist device is used in patients awaiting heart transplantation

A nurse is preparing to administer digoxin [Lanoxin] to a patient. The patient's heart rate is 62 beats per minute, and the blood pressure is 120/60 mm Hg. The last serum electrolyte value showed a potassium level of 5.2 mEq/L. What will the nurse do? a. Contact the provider to request an increased dose of digoxin. b. Give the dose of digoxin and notify the provider of the potassium level. c. Request an order for a diuretic. d. Withhold the dose and notify the provider of the heart rate.

b. Give the dose of digoxin and notify the provider of the potassium level. The patient's serum potassium level is above normal limits, but only slightly. An elevated potassium level can reduce the effects of digoxin, so there is no risk of toxicity. There is no indication that an increased dose of digoxin is needed. There is no indication for a diuretic. The heart rate is acceptable; doses should be withheld if the heart rate is less than 60 beats per minute.

A nurse is discussing heart failure with a group of nursing students. Which statement by a student reflects an understanding of how compensatory mechanisms can compound existing problems in patients with heart failure? a. "An increase in arteriolar tone to improve tissue perfusion can decrease resistance." b. "An increase in contractility to increase cardiac output can cause pulmonary edema." c. "When the heart rate increases to increase cardiac output, it can prevent adequate filling of the ventricles." d. "When venous tone increases to increase ventricular filling, an increase in arterial pressure occurs."

c. "When the heart rate increases to increase cardiac output, it can prevent adequate filling of the ventricles." The heart rate increases to improve cardiac output, but it may prevent adequate ventricular filling. An increase in arteriole tone improves tissue perfusion but also increases both the resistance to the pumping of the heart and the cardiac workload. Increased contractility helps improve cardiac output but is detrimental because it increases the oxygen demand of the heart. An increase in venous tone improves ventricular filling, but as the ventricles fail, blood can back up and cause pulmonary edema.

A nurse prepares to administer a scheduled dose of digoxin. The nurse finds a new laboratory report showing a plasma digoxin level of 0.7 ng/mL. What action should the nurse take? a. Withhold the drug for an hour and reassess the level. b. Withhold the drug and notify the prescriber immediately. c. Administer Digibind to counteract the toxicity. d. Check the patient's apical pulse, and if it is within a safe range, administer the digoxin.

d. Check the patient's apical pulse, and if it is within a safe range, administer the digoxin. The optimum plasma digoxin range is 0.5 to 0.8 ng/mL. The patient's pulse should be checked before administration, as always, and the digoxin should be administered. The digoxin does not have to be withheld, nor does the prescriber need to be notified. If the digoxin level is demonstrating a trend of increasing, the issue should be discussed in rounds. Digibind is not indicated, because the digoxin level is therapeutic

Which medications are included in first-line therapy for heart failure? (Select all that apply.) a. Agents that inhibit the renin-angiotensin-aldosterone system (RAAS) b. Aldosterone antagonists c. Beta blockers d. Cardiac glycosides e. Diuretics

a. Agents that inhibit the renin-angiotensin-aldosterone system (RAAS) c. Beta blockers e. Diuretics

A patient has heart failure and is taking an ACE inhibitor. The patient has developed fibrotic changes in the heart and vessels. The nurse expects the provider to order which medication to counter this development? a. Aldosterone antagonist b. Angiotensin II receptor blocker (ARB) c. Beta blocker d. Direct renin inhibitor (DRI)

a. Aldosterone antagonist Aldosterone antagonists are added to therapy for patients with worsening symptoms of HF. Aldosterone promotes myocardial remodeling and myocardial fibrosis, so aldosterone antagonists can help with this symptom. ARBs are given for patients who do not tolerate ACE inhibitors. Beta blockers do not prevent fibrotic changes. DRIs are not widely used.

The potassium-sparing diuretic spironolactone [Aldactone] prolongs survival and improves heart failure symptoms by which mechanism? a. Blocking aldosterone receptors b. Increasing diuresis c. Reducing venous pressure d. Reducing afterload

a. Blocking aldosterone receptors Spironolactone prolongs survival in patients with HF primarily by blocking receptors for aldosterone. Spironolactone cause only minimal diuresis. It does not reduce afterload, and it does not reduce venous pressure enough to prolong survival, because it causes only minimal diuresis.

A patient has been taking digoxin [Lanoxin] 0.25 mg, and furosemide [Lasix] 40 mg, daily. Upon routine assessment by the nurse, the patient states, "I see yellow halos around the lights." The nurse should perform which action based on this assessment? a. Check the patient for other symptoms of digitalis toxicity. b. Withhold the next dose of furosemide. c. Continue to monitor the patient for heart failure. d. Document the findings and reassess in 1 hour.

a. Check the patient for other symptoms of digitalis toxicity. Yellow halos around lights indicate digoxin toxicity. The use of furosemide increases the risk of hypokalemia, which in turn potentiates digoxin toxicity. The patient should also be assessed for headache, nausea, and vomiting, and blood should be drawn for measurement of the serum digoxin level. The nurse should not withhold the dose of furosemide until further assessment is done, including measurement of a serum digoxin level. No evidence indicates that the patient is in worsening heart failure. Documentation of findings is secondary to further assessment and prevention of digoxin toxicity.

A patient with volume overload begins taking a thiazide diuretic. The nurse will tell the patient to expect which outcome when taking this drug? a. Improved exercise tolerance b. Increased cardiac output c. Prevention of cardiac remodeling d. Prolonged survival

a. Improved exercise tolerance Diuretics help reduce fluid volume overload, which, by reducing pulmonary edema, can improve exercise tolerance. Diuretics do not improve cardiac output. ACE inhibitors are used to prevent cardiac remodeling and to improve long-term survival.

A patient with heart failure who has been given digoxin [Lanoxin] daily for a week complains of nausea. Before giving the next dose, the nurse will: a. assess the heart rate (HR) and give the dose if the HR is greater than 60 beats per minute. b. contact the provider to report digoxin toxicity. c. request an order for a decreased dose of digoxin. d. review the serum electrolyte values and withhold the dose if the potassium level is greater than 3.5 mEq/L.

a. assess the heart rate (HR) and give the dose if the HR is greater than 60 beats per minute. Anorexia, nausea, and vomiting are the most common adverse effects of digoxin and should cause nurses to evaluate for more serious signs of toxicity. If the HR is greater than 60 beats per minute, the dose may be given. Nausea by itself is not a sign of toxicity. A decreased dose is not indicated. A serum potassium level less than 3.5 mEq/L is an indication for withholding the dose.

A patient with Stage C heart failure (HF) who has been taking an ACE inhibitor, a beta blocker, and a diuretic begins to have increased dyspnea, weight gain, and decreased urine output. The provider orders spironolactone [Aldactone]. The nurse will instruct the patient to: a. avoid potassium supplements. b. monitor for a decreased heart rate. c. take extra fluids. d. use a salt substitute instead of salt.

a. avoid potassium supplements. Spironolactone is added to therapy for patients with worsening symptoms of HF. Because spironolactone is a potassium-sparing diuretic, patients should not take supplemental potassium. Patients taking digoxin need to monitor their heart rate. Extra fluids are not indicated. Salt substitutes contain potassium.

A patient newly diagnosed with heart failure is admitted to the hospital. The nurse notes a pulse of 90 beats per minute. The nurse will observe this patient closely for: a. decreased urine output. b. increased blood pressure. c. jugular vein distension. d. shortness of breath.

a. decreased urine output. As the heart rate increases, ventricular filling decreases, and cardiac output and renal perfusion decrease. Tachycardia does not elevate blood pressure. Jugular vein distension and shortness of breath occur with fluid volume overload.

A patient asks a nurse why he cannot use digoxin [Lanoxin] for his heart failure, because both of his parents used it for HF. The nurse will explain that digoxin is not the first-line therapy for which reason? a. It causes tachycardia and increases the cardiac workload. b. It does not correct the underlying pathology of heart failure. c. It has a wide therapeutic range that makes dosing difficult. d. It may actually shorten the patient's life expectancy.

b. It does not correct the underlying pathology of heart failure. Digoxin improves cardiac output, alters electrical effects, and helps to decrease sympathetic outflow from the central nervous system (CNS) through its neurohormonal effects; however, it does not alter the underlying pathology of heart failure or prevent cardiac remodeling. Digoxin causes bradycardia and increases the cardiac workload by increasing contractility. It has a narrow therapeutic range and many adverse effects. Digoxin does not improve life expectancy; in women it may actually shorten life expectancy.

Which are expected effects of cardiac glycosides? (Select all that apply.) a. Decreased cardiac output b. Decreased force of contraction c. Decreased heart rate d. Modulation of neurohormonal systems e. Positive inotropic effects

c. Decreased heart rate d. Modulation of neurohormonal systems e. Positive inotropic effects

A patient with chronic hypertension is admitted to the hospital. During the admission assessment, the nurse notes a heart rate of 96 beats per minute, a blood pressure of 150/90 mm Hg, bibasilar crackles, 2+ pitting edema of the ankles, and distension of the jugular veins. The nurse will contact the provider to request an order for which medication? a. ACE inhibitor b. Digoxin [Lanoxin] c. Furosemide [Lasix] d. Spironolactone [Aldactone]

c. Furosemide [Lasix] This patient shows signs of fluid volume overload and needs a diuretic. Furosemide is a loop diuretic, which can produce profound diuresis very quickly even when the glomerular filtration rate (GFR) is low. An ACE inhibitor will not reduce fluid volume overload. Digoxin has a positive inotropic effect on the heart, which may improve renal perfusion, but this is not its primary effect. Spironolactone is a potassium-sparing diuretic with weak diuresis effects; it is used in conjunction with other diuretics to improve electrolyte balance.

A patient is taking a thiazide diuretic for hypertension and quinidine to treat a dysrhythmia. The prescriber orders digoxin 0.125 mg to improve this patient's cardiac output. The nurse should contact the provider to request: a. adding spironolactone [Aldactone]. b. reducing the dose of digoxin. c. discontinuing the quinidine. d. giving potassium supplements.

c. discontinuing the quinidine. Quinidine can cause plasma levels of digoxin to rise; concurrent use of quinidine and digoxin is contraindicated. There is no indication for adding spironolactone unless this patient's potassium level is elevated. The dose of digoxin ordered is a low dose. Potassium supplements are contraindicated with digoxin.

A patient is taking enalapril [Vasotec]. The nurse understands that patients taking this type of drug for heart failure need to be monitored carefully for: a. hypernatremia. b. hypertension. c. hyperkalemia. d. hypokalemia.

c. hyperkalemia. One of the principal effects of angiotensin-converting enzyme (ACE) inhibitors is hyperkalemia, which is due to decreased aldosterone release arising from blockage of angiotensin II. There is no indication that careful monitoring of sodium for increased levels is indicated. Vasotec is indicated for heart failure, not hypertension. The drug therapy should be monitored to ascertain its effectiveness, but hyperkalemia is the main concern. Hyperkalemia, not hypokalemia, is a concern because of the decreased aldosterone release that occurs with blockage of angiotensin II.

A patient with heart failure who takes a thiazide diuretic and digoxin [Lanoxin] is admitted for shortness of breath. The patient's heart rate is 66 beats per minute, and the blood pressure is 130/88 mm Hg. The serum potassium level is 3.8 mEq/L, and the digoxin level is 0.8 ng/mL. The nurse admitting this patient understands that the patient: a. has digoxin toxicity. b. is showing signs of renal failure. c. is experiencing worsening of the disease. d. needs a potassium-sparing diuretic.

c. is experiencing worsening of the disease. This patient has a normal serum potassium level, and the digoxin level is normal. The patient is showing signs of pulmonary edema, which indicates progression of heart failure. The digoxin level is within normal limits, and the heart rate is above 60 beats per minute, so digoxin toxicity is not likely. There is no sign of renal failure. A potassium-sparing diuretic is not indicated.

A patient with heart failure who has been taking an ACE inhibitor, a thiazide diuretic, and a beta blocker for several months comes to the clinic for evaluation. As part of the ongoing assessment of this patient, the nurse will expect the provider to evaluate: a. complete blood count. b. ejection fraction. c. maximal exercise capacity. d. serum electrolyte levels.

d. serum electrolyte levels. Patients taking thiazide diuretics can develop hypokalemia, which can increase the risk for dysrhythmias; therefore, the serum electrolyte levels should be monitored closely. A complete blood count is not recommended. This patient is taking the drugs recommended for patients with Stage C heart failure; although the patient's quality of life and ability to participate in activities should be monitored, routine measurement of the ejection fraction and maximal exercise capacity is not recommended.