A nurse is planning to administer mannitol to a client who has heart failure and pulmonary edema. Which of the following actions should the nurse take before giving the medication?

The correct answer is choice B. “I can walk farther without getting tired.” This statement indicates a therapeutic effect of metoprolol, which is a beta-blocker that reduces the heart rate, blood pressure, and the workload of the heart.This helps to improve the blood flow and oxygen delivery to the heart and other organs, and reduces the symptoms of heart failure such as fatigue, dyspnea, and edema.

Choice A is wrong because “I have less swelling in my ankles.” This statement indicates a possible effect of a diuretic, which is a medication that reduces fluid retention and edema by increasing urine output.Metoprolol does not have a direct diuretic effect, although it may indirectly reduce fluid accumulation by improving cardiac function.

Choice C is wrong because “I don’t have chest pain anymore.” This statement indicates a possible effect of a nitrate, which is a medication that dilates the blood vessels and reduces the oxygen demand of the heart.Metoprolol may also help to prevent or treat angina by lowering the heart rate and blood pressure, but it is not the primary medication for chest pain relief.

Choice D is wrong because “I can breathe better at night.” This statement indicates a possible effect of an oxygen therapy, which is a treatment that delivers supplemental oxygen to the lungs and improves gas exchange.Metoprolol may also help to reduce dyspnea by improving cardiac function and reducing pulmonary congestion, but it is not the primary treatment for respiratory distress.

Diuretics are drugs that increase the excretion of water and sodium by the kidneys, reducing blood volume and blood pressure.Diuretics lower blood pressure by dilating peripheral arterioles and decreasing blood volume by increasing the excretion of sodium and water.

Choice A is wrong because angiotensin-converting enzyme (ACE) inhibitors do not increase the excretion of water and sodium by the kidneys.ACE inhibitors block the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor and stimulator of aldosterone secretion.By reducing angiotensin II levels, ACE inhibitors lower blood pressure by dilating blood vessels and decreasing sodium and water retention.

Choice C is wrong because adrenergic drugs do not increase the excretion of water and sodium by the kidneys. Adrenergic drugs act on the sympathetic nervous system, which regulates heart rate, blood pressure, and other functions. Depending on the type and location of adrenergic receptors, adrenergic drugs can have different effects on blood pressure. Some adrenergic drugs can increase blood pressure by stimulating alpha receptors, which cause vasoconstriction.Other adrenergic drugs can decrease blood pressure by stimulating beta receptors, which cause vasodilation and decreased cardiac output.

Choice D is wrong because direct acting vasodilators do not increase the excretion of water and sodium by the kidneys. Direct acting vasodilators are drugs that relax the smooth muscle of blood vessels, causing them to widen and lower blood pressure.Direct acting vasodilators do not affect the renin-angiotensin-aldosterone system or the sympathetic nervous system, which regulate sodium and water balance.