Cardiac Medicine Certification (CMC) Practice Exam

What is an expected outcome of diuretic therapy in patients with heart failure?

1. Increase in peripheral edema

2. Decrease in central venous pressure

3. Increase in blood volume

4. Decreased oxygen saturation

The correct answer is: Decrease in central venous pressure

Diuretic therapy in patients with heart failure works primarily by promoting the excretion of sodium and water through the kidneys, leading to a reduction in blood volume. This process alleviates fluid overload, a common issue in heart failure, which can cause various complications. As the blood volume decreases, there is a corresponding decrease in central venous pressure. Central venous pressure reflects the amount of blood returning to the heart, and in heart failure patients, this pressure can be elevated due to fluid accumulation. By effectively managing this fluid load, diuretics help to lower central venous pressure, which is significant in assisting the heart to function more efficiently and improving symptoms related to congestion. In contrast, outcomes such as an increase in peripheral edema, an increase in blood volume, or decreased oxygen saturation do not align with the intended effects of diuretic therapy. The goal is to reduce excess fluid and improve the overall cardiovascular status of the patient. Thus, monitoring central venous pressure can be a critical marker of the effectiveness of diuretic therapy in these patients.