A nurse is reviewing the laboratory results for a female client who is receiving furosemide and digoxin. Which of the following findings should the nurse recognize increases the client's risk for developing digoxin toxicity?

Rationale: A. Potassium 3.1 mEq/L (3.5 to 5 mEq/L): Hypokalemia increases the risk of digoxin toxicity because low potassium levels enhance digoxin’s effects on the myocardium, potentially leading to arrhythmias and other toxic effects. Monitoring electrolytes is crucial for clients taking digoxin, especially when on diuretics like furosemide. B. WBC count 12,000/mm³ (5,000 to 10,000/mm³): An elevated WBC may indicate infection or inflammation but does not directly influence digoxin toxicity. This finding requires assessment but is not a risk factor for digoxin-related complications. C. Fasting glucose 150 mg/dL (74 to 106 mg/dL): Elevated glucose reflects hyperglycemia but does not affect digoxin levels or toxicity risk. It should be managed separately according to the client’s metabolic needs. D. Triglycerides 140 mg/dL (35 to 135 mg/dL): Mildly elevated triglycerides are a cardiovascular risk factor but do not directly increase the likelihood of digoxin toxicity. Lipid management is a separate consideration.