A nurse is reviewing a client's CBC findings and discovers that the client's platelet count is 9,000/mm3. The nurse should monitor the client for which of the following conditions?

A. Hemoglobin levels are important for assessing oxygen-carrying capacity of the blood. While anemia can affect tissue oxygenation and exacerbate symptoms in heart failure, it is not directly related to the risk of digoxin toxicity.
B. Creatinine levels are used to assess kidney function. Impaired kidney function can affect the clearance of digoxin from the body, potentially increasing the risk of toxicity. However, potassium levels have a more direct impact on the risk of digoxin toxicity.
C. BUN levels are also used to assess kidney function. Similar to creatinine, impaired kidney function can affect digoxin clearance, but potassium levels are more directly related to the risk of digoxin toxicity.
D. Potassium levels are critical because hypokalemia (low potassium) can predispose the client to digoxin toxicity. Digoxin competes with potassium for binding sites on the sodium-potassium ATPase pump in cardiac cells. When potassium levels are low, digoxin can bind more readily to these pumps, leading to increased toxicity and potentially life-threatening arrhythmias such as ventricular tachycardia or ventricular fibrillation.

A. Furosemide can increase serum uric acid levels, leading to hyperuricemia. This occurs due to the drug's effects on renal excretion of uric acid. Hyperuricemia can predispose the client to gouty arthritis or kidney stones.
B. Furosemide typically leads to sodium loss (natriuresis) rather than hypernatremia. It is a loop diuretic that inhibits sodium and chloride reabsorption in the ascending loop of Henle in the kidneys, promoting diuresis and reducing fluid overload.
C. Furosemide-induced diuresis can cause loss of chloride ions along with sodium, potentially leading to hypochloremia rather than hyperchloremia. Hyperchloremia is less common unless there are other contributing factors such as concurrent administration of saline solutions or underlying conditions.
D. Furosemide does not typically cause hypercalcemia. In fact, it can lead to mild hypocalcemia due to increased urinary calcium excretion. Loop diuretics like furosemide impair calcium reabsorption in the kidneys, which can lead to calcium wasting.