The nurse, recognizing that digitalis preparations promote diuresis, should evaluate patients for a depletion… - JODHPUR AIIMS SNO-2018

JODHPUR AIIMS SNO-2018

Pharmacology

Medium

Appeared in: JODHPUR AIIMS SNO-2018

Explanation

Digitalis preparations can have a diuretic effect, leading to increased excretion of potassium through the urine.
This loss of potassium can cause hypokalemia (low serum potassium).
Hypokalemia is a major risk factor for digitalis toxicity because it enhances the binding of digoxin to its receptor site (the Na+/K+-ATPase pump) in cardiac cells.
This increased binding potentiates the drug's effects, which can lead to dangerous cardiac arrhythmias.
Therefore, nurses must closely monitor potassium levels in patients receiving digitalis.

Option A: Phosphate levels are not directly or significantly affected by the diuretic action of digitalis preparations.
Option B: Depletion of calcium (hypocalcemia) is not the concern with digitalis. Instead, high calcium levels (hypercalcemia) increase the risk of digitalis toxicity.
Option C: While diuresis can cause some sodium loss (hyponatremia), it is not the primary electrolyte imbalance that potentiates digitalis toxicity.

Clinical Relevance

Nursing practice connection: Knowing Electrolyte Imbalance and Digitalis Toxicity helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
A core nursing responsibility when administering digitalis is to prevent, recognize, and manage toxicity. Monitoring potassium is a critical patient safety measure.
Patients on digitalis are often also prescribed potassium-wasting diuretics (like furosemide or hydrochlorothiazide), which dramatically increases the risk of hypokalemia and subsequent toxicity.
What if? If a patient on digoxin develops vomiting or diarrhea, the risk of hypokalemia and digitalis toxicity increases significantly due to gastrointestinal fluid and electrolyte losses. The nurse must notify the provider, monitor the patient's electrolyte levels closely, and assess for signs of toxicity.

How to Approach the Question

First, identify the drug class mentioned in the question: digitalis preparations (e.g., digoxin).
Recall the key actions and side effects of this drug. Digitalis increases cardiac contractility but has a narrow therapeutic window and a high risk of toxicity.
Analyze the clinical effect mentioned: 'promote diuresis'. Diuresis means increased urine output, which leads to the loss of water and electrolytes.
Connect the drug's toxicity profile with the side effect. Ask yourself, 'Which electrolyte imbalance is most famous for increasing the risk of digitalis toxicity?'
Recall the classic interaction: low potassium (hypokalemia) sensitizes the heart to digitalis, greatly increasing the risk of toxicity.
Evaluate the options based on this knowledge. Potassium depletion is the most significant risk, making it the correct answer.

Concept Tested & Keywords

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