Question

a nurse is reviewing the laboratory results of a client who is taking digoxin for heart failure. which of the following results should the nurse report to the provider due to it increasing the risk for digoxin toxicity?

decreased platelet count
decreased albumin level
decreased hematocrit
decreased potassium level

Explanation:

Analyze the mechanism of digoxin binding

Using the Cardiac Glycosides knowledge point

$$ \text{Digoxin competes with } \text{K}^+ \text{ for binding sites on the } \text{Na}^+/\text{K}^+\text{-ATPase pump.} $$

Determine the effect of low potassium

Using the Digoxin Toxicity knowledge point

$$ \downarrow [\text{K}^+] \implies \uparrow \text{Digoxin binding} \implies \uparrow \text{Risk of toxicity} $$

Evaluate the remaining options

• Decreased platelet count (thrombocytopenia) does not directly alter digoxin binding or clearance.
• Decreased albumin level can affect highly protein-bound drugs, but digoxin is only moderately protein-bound (\approx 25\%) and its toxicity is not primarily driven by hypoalbuminemia.
• Decreased hematocrit (anemia) does not alter digoxin pharmacokinetics or pharmacodynamics.
• Decreased potassium level (hypokalemia) directly sensitizes the myocardium to digoxin, significantly increasing the risk of life-threatening arrhythmias.

Answer:

• Decreased platelet count
• Decreased albumin level
• Decreased hematocrit
• Decreased potassium level (Correct answer)