Which of the following statements indicates the nurse has the right understanding of the drug Digoxin while explaining its action to the patient?

Appeared in: RML MAINS 2025

Explanation

Digoxin is a cardiac glycoside that exerts a positive inotropic effect, meaning it increases the force and velocity of myocardial contraction.
This action is achieved by inhibiting the Na+/K+-ATPase pump in cardiac muscle cells.
Inhibition of the pump leads to an increase in intracellular sodium, which then promotes an increase in intracellular calcium.
The elevated intracellular calcium enhances the contractility of the heart muscle, improving cardiac output, especially in heart failure.

Option A: This statement is incorrect because Digoxin has a negative chronotropic effect, meaning it slows down the heart rate, not increases it. This is a key safety consideration.
Option B: This is incorrect. Digoxin is not classified as an antihypertensive medication. Its primary roles are in managing heart failure and certain cardiac arrhythmias.
Option D: This is incorrect. Digoxin does not directly act on the coronary arteries to increase blood flow. While improved cardiac output might indirectly improve perfusion, it is not its primary mechanism.

Clinical Relevance

Nursing practice connection: Use the key finding related to Pharmacology: Mechanism of Action of Digoxin to guide bedside assessment, documentation, and the next nursing action.
A critical nursing responsibility before administering Digoxin is to measure the apical pulse for a full minute. The medication must be held and the provider notified if the pulse is below 60 bpm in an adult, as this indicates bradycardia, a potential sign of toxicity.
Hypokalemia (low potassium) significantly increases the risk of Digoxin toxicity. Nurses must diligently monitor serum potassium levels and be vigilant for signs of toxicity like nausea, vomiting, anorexia, and visual disturbances (yellow/green halos).
What if? If a patient on Digoxin presents with a potassium level of 3.1 mEq/L (normal: 3.5-5.0) and complains of nausea, the nurse's priority action is to hold the Digoxin dose and immediately report these findings to the healthcare provider, as they are classic signs of impending toxicity.

How to Approach the Question

First, identify the core subject of the question, which is the pharmacological action of the drug Digoxin.
Read the question stem carefully: it asks for the statement that shows a 'right understanding' of Digoxin's action.
Evaluate each option based on your knowledge of cardiac glycosides.
Option A (increases heart rate) is incorrect; Digoxin slows the heart rate (negative chronotropy).
Option B (reduces blood pressure) is incorrect; it's not a primary antihypertensive.
Option C (increases contractility) is the definition of a positive inotrope, which is the primary therapeutic action of Digoxin.

Concept Tested & Keywords

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E6 Pharmacology Nursing Lilley 11e Part 2 p. 73-75

E6 Pharmacology KD Tripathi Essentials 9e Part 2 p. 188-190

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