Medical Surgical Fluids and Hormones #5

Question

A client in heart failure has been put on lisinopril. Which response by the nurse is best when asked by the client how lisinopril works?

Answers

  1. “Lisinopril prevents an enzyme in your blood from producing angiotensin II so that aldosterone is not produced, and your heart does not have to work as hard to circulate the blood.”
    • Rationale:

      This answer is correct because it is the action of an ACE inhibitor. ACE inhibitors prevent angiotensin II from releasing aldosterone. This results in the kidneys excreting sodium and water, lowering the fluid volume and reducing the workload of the heart.

  2. “Lisinopril blocks the effect of angiotensin II and the blood vessels then widen so that blood can flow more easily and lower the blood pressure.”
    • Rationale:

      This answer is not correct because this is the action of an angiotensin II receptor blocker (ARB). ARBs block the effect of angiotensin II by preventing angiotensin II from binding to angiotensin II receptors on muscles surrounding blood vessels, so that the blood vessels widen and blood pressure is reduced.

  3. “Lisinopril prevents release of aldosterone so that the kidneys can excrete fluid and sodium without losing potassium.”
    • Rationale:

      This answer is not correct because this is the action of a potassium-sparing diuretic. Diuretics such as these prevent the release of aldosterone so that the kidneys can release the retained sodium and fluid without losing potassium.

  4. “Lisinopril slows the movement of calcium into the cells of the heart, dilating the blood vessels and making it easier for the heart to pump blood.”
    • Rationale:

      This answer is not correct because this would be what a calcium channel blocker does. It slows the movement of calcium into the cells of the heart, dilating the blood vessels and making it easier for the heart to pump blood, thus reducing the blood pressure.

Overview

Lisinopril is an angiotensin converting enzyme (ACE) inhibitor which prevents angiotensin II from stimulating aldosterone release. This prevents the kidneys from retaining sodium and water.

Explanation

Learning Outcomes

Lisinopril is an angiotensin converting enzyme (ACE) inhibitor which prevents angiotensin II from stimulating aldosterone release. This prevents the kidneys from retaining sodium and water. The release of sodium and water helps reduce the workload of the heart, thus lowering the blood pressure. ARBs would be the next step of action if ACE inhibitors fail. ARBs prevent angiotensin II from binding to angiotensin II receptors on muscles surrounding blood vessels, so that the blood vessels widen and blood pressure is reduced. The last resort in preventing sodium and water retention would be potassium-sparing diuretics. Potassium-sparing diuretics prevent the release of aldosterone so that the kidneys can release the retained sodium and fluid without losing potassium.

Test Taking Tip

Know your cardiac drug classifications and how they work.

Video Rationale