Which drug blocks the binding of angiotensin II to its receptors on blood vessels and adrenal glands, preventing its vasoconstrictive and aldosterone-stimulating effects?

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.

Nifedipine is a calcium channel blocker that lowers blood pressure by relaxing the blood vessels and reducing the workload of the heart.

The following instructions should be included in the teaching:

• Avoid drinking alcohol while taking this medication.Alcohol can increase the risk of side effects such as dizziness, flushing, headache, and low blood pressure.

• Monitor your blood pressure and pulse regularly.This will help to evaluate the effectiveness of the medication and detect any abnormal changes.Normal blood pressure for adults is less than 130/80 mm Hg and normal pulse rate is 60 to 100 beats per minute.

• Report any swelling in your ankles or feet to your provider.This can be a sign of fluid retention or heart failure, which are possible complications of nifedipine.

• Do not stop taking this medication abruptly.This can cause a rebound increase in blood pressure and chest pain.The dose should be tapered gradually under the supervision of the provider.

Choice E is wrong because chewing or crushing the sustained-release tablet can cause too much of the drug to be released at once, which can lead to overdose or severe side effects.

The tablet should be swallowed whole with a glass of water.