Chapter 44: Cardiotonic Agents

A nurse caring for a patient with atrial fibrillation who is started on digitalis is required to monitor plasma digitalis levels in the patient's blood. Which plasma level of digitalis indicates that the nurse should report to the practitioner? 1.6 nanograms (ng)/ml 1.8 ng/ml 2 ng/ml 2.2 ng/ml

2.2 ng/ml A plasma digitalis level of more than 2 ng/ml would require the nurse to report to the practitioner; therefore plasma digitalis levels of 2.2 ng/ml indicate digitalis toxicity. In such circumstances, the nurses should immediately report to the practitioner. The therapeutic levels of plasma digitalis are 0.5 to 2 ng/ml.

Nesiritide is a human B-type natriuretic peptide. True False

True

Vasodilators used to treat heart failure include nitrates and ACE inhibitors. True False

True Drug therapies used to treat heart failure include vasodilators, such as angiotensin-converting enzyme (ACE) inhibitors and nitrates, which decrease cardiac workload, relax vascular smooth muscle to decrease afterload, and allow pooling in the veins, thereby decreasing preload of the heart and helping to improve function.

A nurse assessing a client on digoxin observes features of toxicity. Which visual disturbance should the nurse assess for in such clients? Complete loss of vision Double vision Yellow or green vision Difficulty of near vision

Yellow or green vision The visual disturbance the nurse should assess for is yellow or green vision with a white halo. Visual disturbances occur in digoxin toxicity. Blurring of vision and borders around dark objects are the other visual disturbances. Double vision, difficulty of near vision, and complete loss of vision do not occur in digitalis toxicity.

A client with a history of heart failure is being treated with digoxin. The nurse knows that this medication increases the force of contractions of the heart. What effect improves the contractility of the heart? positive chronotropic effect positive inotropic effect negative inotropic effect negative dromotropic effect

positive inotropic effect In heart failure, digoxin exerts cardiotonic or positive inotropic effect that improves the contractility and pumping ability of the heart. A positive chronotropic effect accelerates the rate of the heart, which is not recommended in a client with heart failure. A negative inotropic effect accelerates the heart, which is not recommended in a client with heart failure. A negative dromotropic effect changes the conductivity of muscle fiber, increasing heart rate.

Which would the nurse identify as a cardiac glycoside? Inamrinone Milrinone Digoxin Captopril

Digoxin Peripheral edema

After teaching a class of students about heart failure and drug therapy, the instructor determines that the teaching has been successful when the students identify which drug as most often used as treatment? Digoxin Human B-type natriuretic peptide Nitrate Furosemide

Digoxin Digoxin is the drug most often used to treat heart failure. Human B-type natriuretic peptide, nitrate, or furosemide also may be used, but these drugs are not the ones most commonly used.

The pharmacology instructor is describing medications that increase the contractile force of the heart. Which term describes this effect? Positive chronotropic Positive inotropic Negative inotropic Negative dromotropic

Positive inotropic A positive inotropic effect improves the contractility and pumping ability of the heart.

The nurse identifies the therapeutic range for digoxin as: 3 to 4 ng/mL. 0.8 to 2 ng/mL. 0.1 to 0.9 ng/mL. 2 to 3 ng/mL.

0.8 to 2 ng/mL. Therapeutic digoxin levels are between 0.8 and 2 nanograms/mL. Plasma digoxin levels greater than 2 nanograms/mL are considered toxic.

A male client who is prescribed digoxin asks the nurse how he should take the drug. Which instruction would be most appropriate? "Take the medicine with an antacid at any time of the day." "Take the drug after eating your breakfast." "Eat a small snack just before taking the drug." "Take the drug on an empty stomach at the same time each day."

"Take the drug on an empty stomach at the same time each day." Food and antacids interfere with the absorption of the drug. Digoxin should be taken on an empty stomach at approximately the same time each day. If the client takes an antacid, the client should separate the dose of antacid and digoxin by 2 to 4 hours.

A client is receiving digoxin. The nurse monitors the client's digoxin level. Which level should the nurse interpret as therapeutic? 1.5 ng/mL 2.2 ng/mL 2.5 ng/mL 3.1 ng/mL

1.5 ng/mL Therapeutic digoxin levels range from 0.5 ng/mL to 2.0 ng/mL. A level of 1.5 ng/mL would be considered therapeutic.

A nurse must immediately report serum digoxin levels greater than: 2.0 nanograms/mL. 1.0 nanograms/mL. 0.5 nanograms/mL. 3.0 nanograms/mL.

2.0 nanograms/mL. A nurse must immediately report serum digoxin levels greater than 2.0 nanograms/mL.

A client experiences nausea and visual disturbances when taking digoxin (Lanoxin). The nurse would anticipate the client's digitalis level to be: 0.2 nanograms/mL 1.3 nanograms/mL 2.7 nanograms/mL 1.7 nanograms/mL

2.7 nanograms/mL Therapeutic drug levels of digoxin are between 0.8 and 2 nanograms/ mL. Plasma digoxin levels greater than 2 nanograms/mL are considered toxic and the client may experience signs and symptoms of toxicity.

A female client presents to the emergency department with nausea, vomiting, and a heart rate of 45 beats per minute. Her husband states that she takes digoxin, Lasix, and nitroglycerin for chest pain. Laboratory results confirm digoxin toxicity. The nurse would expect the health care provider to order what medication to treat the bradycardia? Atropine Nifedipine Nitroglycerin Nesiritide

Atropine Atropine or isoproterenol, used in the management of bradycardia or conduction defects, may be administered to clients with digoxin toxicity.

A male client states that he is seeing halos around lights. The client takes digoxin (Lanoxin) by mouth every day. The health care provider orders the client to have serum digoxin level drawn. Which of the digoxin levels indicate the client is experiencing toxicity? 0.5 nanograms per milliliter 1.0 nanograms per milliliter 2.0 nanograms per milliliter 4.0 nanograms per milliliter

4.0 nanograms per milliliter Therapeutic serum levels of digoxin are 0.5 to 2 nanograms per milliliter; toxic serum levels are above 2.0.

A male client has called the clinic because he is taking digoxin and is concerned about his pulse rate. The nurse should tell the client to hold the medication if he reports a pulse rate of: 52 beats/minute. 84 beats/minute. 78 beats/minute. 66 beats/minute.

52 beats/minute. A pulse rate below 60 beats/minute would be an indication to withhold the medication.

What is the most accurate method for preventing adverse effects associated with the use of digoxin? Teach clients to take their digoxin in divided doses with each meal. Assess the client's heart rate and hold administration if it is less than 60. Teach clients the signs and symptoms of heart failure. Monitor therapeutic effects based on echocardiogram results.

Assess the client's heart rate and hold administration if it is less than 60. Clients should be taught to hold their digoxin if their heart rate is less than 60 (or some other defined heart rate). Divided doses are not normally used and an awareness of heart failure does not preclude adverse effects of digoxin.

The home care nurse sees a client for the first time. The client has crackles in the lower lobes of the lungs, an audible S3, and pitting edema in the feet and ankles. What condition is the client experiencing? Pneumonia Liver disease Congestive heart failure Myocardial infarction

Congestive heart failure Heart failure has been referred to as congestive heart failure because frequently there is congestion in the lungs and peripheral tissues. The client has pitting edema of the feet and ankles, which is not noted with pneumonia. Liver disease can lead to the development of congestive heart failure but is not the cause of the symptoms of congestion. The client is not presenting with myocardial infarction symptoms.

A nurse is caring for a patient admitted to the intensive care unit because of heart failure. The patient is prescribed digoxin. Which nursing diagnosis would be appropriate for this patient? Risk for Hyperthyroidism related to adverse effects of drug therapy Decreased Cardiac Output related to altered cardiac function Acute Pain and Headache related to adverse effects of the drug therapy Risk of Constipation related to adverse effects of the drug therapy

Decreased Cardiac Output related to altered cardiac function Use of digoxin increases the risk for Decreased Cardiac Output related to altered cardiac function from the drug therapy. The use of digoxin does not pose a risk for acute pain, headache, hyperthyroidism, or constipation.

A client is being treated for hypokalemia. The client's current medications include Inderal, digoxin, and Coumadin. The client reports nausea, abdominal discomfort, and visual changes. Which problem would the nurse suspect? Heart failure Myocardial infarction Digitalis toxicity Acute renal failure

Digitalis toxicity Individuals with hypokalemia can develop digitalis toxicity even when digoxin levels are not considered elevated. Signs of toxicity include potentially life-threatening heart rhythm disturbances, ranging from very slow to rapid ventricular rhythms. Other side effects include nausea, vomiting, loss of appetite, abdominal discomfort, blurred vision, and mental changes.

A 58-year-old man is admitted to the emergency department. A diagnosis of severe digoxin toxicity is made. Bradycardia is present, and an electrocardiogram (ECG) confirms toxicity. The nurse will administer which drug? Furosemide Digoxin immune fab Captopril Dopamine

Digoxin immune fab Digoxin immune fab is used as the antidote to digoxin toxicity. The other drugs would not be used to treat digoxin toxicity. The patient could be taking furosemide as part of the drug regimen for heart failure.

A patient is experiencing nausea and visual disturbances when taking digoxin (Lanoxin). Which medication will be administered? Acetylsalicylic acid (aspirin) Nesiritide (Natrecor) Felbamate (Felbatol) Digoxin immune fab (Digibind)

Digoxin immune fab (Digibind) A patient who has nausea and visual changes while taking digoxin will most likely be administered digoxin immune fab (Digibind). Acetylsalicylic acid is not administered for digoxin toxicity. Nesiritide is not administered when the patient is experiencing digoxin toxicity. Felbamate is administered for the treatment of seizures.

Which symptoms would most likely be present in a client with left ventricular dysfunction? (Select all that apply.) Dyspnea Moist cough Restlessness Peripheral edema Neck vein distention

Dyspnea Moist cough Restlessness The symptoms of left ventricular dysfunction include dyspnea, moist cough, production of frothy, pink sputum, orthopena, restlessness, and anxiety.

The nurse is teaching a female patient about newly prescribed digoxin. The patient tells the nurse that she occasionally uses herbal therapies. The nurse should caution the patient against using therapies that involve which herbs? Black cohosh Ginseng Saw palmetto Valerian

Ginseng Patients taking digoxin should avoid licorice, ginseng, or hawthorn because concomitant use of those products can increase drug effects or cause toxicity. In general, patients taking any medication should discuss all herbal remedies with a health care provider to assess for potential interactions.

Milrinone (Primacor) is a miscellaneous inotropic drug used in the short-term management of heart failure. What is the only way this drug is approved to be administered? Intravenously Intramuscularly Subcutaneously Orally

Intravenously Milrinone (Primacor) is only to be given intravenously.

The client's digoxin level is 0.125. How does the nurse interpret this level? Normal Elevated Toxic Low

Low The normal digoxin level is 0.5 to 2.0 ng/mL. Serum levels greater than 2 ng/mL are toxic; however, toxicity may occur at any serum level.

The nurse is caring for a patient receiving cardiotonic drugs. The patient has edema. Which intervention should be taken to alleviate edema? Auscultation of the lungs Measurement of intake and output Observation of respiratory rate Observation of pulse rate

Measurement of intake and output Measurement of intake and output is a nursing intervention related to the edema in the patient receiving cardiotonic drugs. Auscultation of the lungs, observation of respiratory rate, and observation of pulse rate are interventions not related to edema in the patient.

The nurse is preparing to administer digoxin to a 9-month-old infant. What must the nurse do prior to administration of this medication? Monitor the infant's respiratory rate Monitor the infant's blood pressure Monitor the infant's temperature Monitor the infant's apical pulse

Monitor the infant's apical pulse The nurse must assess the client's apical pulse before administering digoxin because it has a narrow therapeutic index and can cause the heart rate to go too low, so the nurse takes the apical pulse and holds the medication if it is below a certain level (depending upon age of the client.)

A nurse is caring for a 66-year-old female client who is receiving digoxin. When preparing to administer a dose, the nurse observes that the client's apical pulse rate is 55 bpm. What is the appropriate action to take? Omit the dose and contact the health care provider. Give the dose and contact the health care provider. Reduce the dose and contact the health care provider. Omit the dose and inform the oncoming nurse at the next shift change.

Omit the dose and contact the health care provider. Bradycardia is a potential adverse effect of digoxin. Nurses should assess the client's apical pulse before each dose. If the rate is lower than 60 bpm in an adult client, the nurse should omit the dose and notify the provider.

When dosing digoxin (Lanoxin), which factors are considered? (Select all that apply.) Patient lean body weight Patient age Renal function Pharmacokinetics Pharmacodynamics

Patient lean body weight Patient age Renal function Pharmacokinetics Pharmacodynamics

After reviewing the signs and symptoms of heart failure, a student demonstrates understanding when the student identifies which finding as associated with right sided heart failure? Peripheral edema Hemoptysis Dyspnea Polyuria

Peripheral edema Peripheral edema would be associated with right-sided heart failure. Hemoptysis, dyspnea, and polyuria would be associated with left-sided heart failure.

Which would a nurse expect to assess if a client is experiencing right-sided heart failure? Wheezing Peripheral edema Hemoptysis Dyspnea

Peripheral edema Peripheral edema would be noted in clients with right-sided heart failure. Wheezing, hemoptysis, and dyspnea would suggest left-sided heart failure.

A nurse is caring for a client who is taking digoxin and a loop diuretic. Which would be most important for the nurse to monitor? Electrocardiogram results Potassium levels Sodium levels Liver enzymes

Potassium levels Although it is important to monitor the client's ECG, it is more important to closely monitor potassium levels when the client is taking a drug that promotes the loss of potassium, such as thiazide or loop diuretics. Hypokalemia increases the effect of digoxin and increases the risk for digoxin toxicity. The client's sodium levels and liver enzyme levels may need to be monitored periodically, but not as closely as potassium levels.

A patient with congestive heart failure has been digitalized. The patient requires long-term digoxin therapy. Which instructions should the nurse provide the patient on discharge? Take the drug with high fiber meals. Report to the center if the pulse is less than 70 bpm. Take antacids promptly to avoid gastric problems. Take the drug regularly without skipping a dose.

Take the drug regularly without skipping a dose. The nurse should instruct the patient to take the drug regularly without skipping a dose. The patient should consult the provider before discontinuing the drug. Taking the drug with high-fiber meals will decrease the absorption of the drug. The patient should be advised to report to the center if the pulse is less than 60 bpm. Antacids should not be taken as it alters the plasma digoxin levels.

A client has an elevated BUN. The client has been prescribed digoxin for heart failure. What aspect of care is the priority regarding this client? The client should be taught to increase sodium in the diet. The dose should be increased when the heart rate is below 60. The dose should be decreased in this client. The dosage should be 1.0 mg per mouth daily.

The dose should be decreased in this client. The dose must be reduced in the presence of renal failure because most of the digoxin is excreted unchanged by the kidneys, leading to drug accumulation and toxicity. The client should be taught to limit sodium intake in the diet. The client's heart rate should remain above 60. If the heart rate falls below 60, the digoxin should be held. The dose of 1.0 mg is too large for a client with altered renal function.

A triage nurse in the emergency department suspects that a 78-year-old patient is experiencing severe digoxin toxicity with significant cardiac dysrhythmia. If the nurse is correct, which action is likely to be taken? The patient's digoxin dosage will be reduced. The patient will be given digoxin immune fab. The patient will be given sodium chloride. The patient will be monitored to see if symptoms resolve without action.

The patient will be given digoxin immune fab. Digoxin is stopped, not merely reduced, in patients experiencing toxicity. If digoxin toxicity is accompanied by serious dysrhythmias, several drugs may be used, including potassium chloride (if serum potassium is low) and digoxin immune fab (if toxicity is serious).

A client is being treated for heart failure. Which is most indicative of improved health status? decreased pitting edema increased skin turgor heart rate of 52 improved sensorium

decreased pitting edema The absence of pitting edema, decreased size of ankles and abdominal girth, and decreased weight improves circulation and increases renal blood flow. The diminished fluid volume is indicative of an improved blood supply to the body tissues. Increased skin turgor indicates that the client is well hydrated and does not have fluid volume excess. A heart rate of 52 is too slow to provide good contractility. Improved sensorium indicates adequate perfusion but is not the most indicative of improved heart failure status.

A client's digoxin level is reported to be 2.2 ng/mL. This result indicates: a subtherapeutic drug level. a therapeutic drug level. digitalis toxicity. a loading dose has been given.

digitalis toxicity. The normal digoxin level is 0.5 to 2.0 ng/mL. Toxic serum levels are greater than 2 ng/mL; however, toxicity may occur at any serum level.

A male client is diagnosed with heart failure. The health care provider orders a loading dose of digoxin. Loading doses are necessary for what reason? Digoxin's short half-life increases the risk for toxicity. The client is at risk for dysthymia with titrated doses. Digoxin's long half-life makes therapeutic serum levels difficult to obtain without loading. Oral digoxin is ineffective for the treatment of heart failure.

Digoxin's long half-life makes therapeutic serum levels difficult to obtain without loading. Digoxin dosages must be interpreted with consideration of specific client characteristics, including age, weight, gender, renal function, general health state, and concurrent drug therapy. Loading or digitalizing doses are necessary for initiating therapy, because digoxin's long half-life makes therapeutic serum levels difficult to obtain without loading. Loading doses should be used cautiously in clients who have taken digoxin within the previous 2 or 3 weeks.

A patient has been prescribed inamrinone. The nurse knows that this drug works by: decreasing cyclic adenosine monophosphate (cAMP). decreasing cardiac output. increasing cardiac preload. increasing cyclic adenosine monophosphate (cAMP).

increasing cyclic adenosine monophosphate (cAMP). By blocking the enzyme phosphodiesterase, phosphodiesterase inhibitors such as inamrinone increase myocardial cell cAMP. The resulting increase in cellular calcium levels leads to a stronger myocardial contraction and prolongs the effects of sympathetic stimulation.