Question 4

Diuretic drugs are prescribed to increase urine flow and decrease total blood volume that must be pumped.

This approach helps to lower blood pressure by reducing the volume of fluid in the bloodstream, which in turn decreases the workload on the heart.

A) To increase urine flow, and to decrease total blood volume that must be pumped

This option is correct as diuretics work by promoting the excretion of water and electrolytes through urine. By increasing urine flow, diuretics effectively reduce total blood volume, which lowers blood pressure and reduces the strain on the cardiovascular system.

B) To decrease urine flow, to increase total blood volume that must be pumped

This option is incorrect because it contradicts the primary function of diuretics. Diuretics are intended to increase urine output, not decrease it, and increasing total blood volume would raise blood pressure rather than lower it.

C) To increase urine flow, and to make the blood less viscous and easier to pump

While increasing urine flow is a correct action of diuretics, this option incorrectly suggests that the purpose is to make blood less viscous. Diuretics primarily aim to reduce blood volume rather than directly affect blood viscosity.

D) To increase urine flow, and to increase the total blood volume that must be pumped

This option is also incorrect as it misrepresents the purpose of diuretics. The goal is not to increase total blood volume but rather to decrease it, thus alleviating high blood pressure.

Conclusion

The rationale for prescribing diuretics in patients with high blood pressure hinges on their ability to increase urine output and reduce total blood volume, which ultimately lowers blood pressure. All other options fail to accurately reflect the mechanism and purpose of diuretic therapy, reinforcing the correctness of Option A.