A nurse is caring for a group of clients. The nurse should monitor which of the following clients for manifestations of hypokalemia? (Select all that apply.)

Choice A rationale Prednisone is a corticosteroid that promotes potassium excretion by the kidneys. It increases the activity of the sodium-potassium pump in renal tubules, leading to increased sodium reabsorption and potassium secretion. This action can result in a significant loss of potassium, putting the client at risk for developing hypokalemia (serum potassium < 3.5 mEq/L). Choice B rationale Torsemide is a loop diuretic that inhibits the reabsorption of sodium and chloride in the loop of Henle. This action leads to increased excretion of not only sodium, chloride, and water, but also potassium. The mechanism is a compensatory increase in potassium secretion in the distal convoluted tubule due to the increased delivery of fluid. Choice C rationale Polystyrene sulfonate is a potassium-binding resin used to treat hyperkalemia, not hypokalemia. It works in the gastrointestinal tract by exchanging sodium ions for potassium ions, which are then excreted in the feces. This medication actively lowers potassium levels and would not be used in a client at risk for hypokalemia. Choice D rationale Spironolactone is a potassium-sparing diuretic. It works by blocking the effects of aldosterone in the distal renal tubules, which promotes sodium and water excretion while preventing potassium and hydrogen ion excretion. This action actually increases serum potassium levels, making it a treatment for hypokalemia, not a cause. Choice E rationale Hydrochlorothiazide is a thiazide diuretic that works in the distal convoluted tubule. It inhibits the sodium-chloride symporter, leading to increased excretion of sodium, chloride, and water. This also indirectly increases potassium excretion, as the increased sodium delivery to the collecting duct stimulates the sodium-potassium exchange pump.