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?

Mannitol is an osmotic diuretic that increases urine output and decreases intracranial pressure and intraocular pressure. The nurse should check the urine output before giving the medication to ensure adequate renal function and prevent fluid overload and electrolyte imbalance. The normal urine output is 0.5 to 1 mL/kg/hr.

Choice B is wrong because checking the blood pressure is not specific to mannitol administration. Mannitol can cause hypotension or hypertension depending on the fluid status of the client, but this is not the priority action before giving the medication.

Choice C is wrong because checking the blood glucose is not relevant to mannitol administration. Mannitol does not affect blood glucose levels.

Choice D is wrong because checking the oxygen saturation is not related to mannitol administration. Mannitol does not affect oxygen saturation levels.

The nurse should monitor the serum potassium level to determine the therapeutic effectiveness of digoxin (Lanoxin), a cardiac glycoside that improves the contractility and pumping ability of the heart. Digoxin has a narrow therapeutic range and can cause toxicity if the serum level is too high or if the patient has hypokalemia (low potassium).Hypokalemia can result from diuretic therapy, which is often prescribed for heart failure patients to reduce fluid overload.

Therefore, the nurse should monitor the serum potassium level and report any abnormal values to the provider.The normal potassium level is 3.5 to 5.0 mEq/L.

Choice B) Serum sodium level is wrong because sodium level is not directly affected by digoxin therapy.

Sodium level may be altered in heart failure patients due to fluid retention or diuretic use, but it does not indicate the effectiveness of digoxin.

Choice C) Serum magnesium level is wrong because magnesium level is not directly affected by digoxin therapy.

Magnesium level may be altered in heart failure patients due to diuretic use or renal impairment, but it does not indicate the effectiveness of digoxin.

Choice D) Serum calcium level is wrong because calcium level is not directly affected by digoxin therapy.

Calcium level may be altered in heart failure patients due to renal impairment or vitamin D deficiency, but it does not indicate the effectiveness of digoxin.