A client with acute heart failure received intravenous furosemide for pulmonary congestion. Which finding best shows that the medication produced the intended effect?

Furosemide relieves pulmonary congestion by removing excess fluid. Rising urine output with clearing crackles shows that effect, while the other findings reflect adverse or unchanged responses.

Quick answer
Greater urine output together with clearing lung sounds shows the drug worked.

Why this is correct
The drug was given for fluid in the lungs, so the outcome must be measured against that problem. Diuresis followed by quieter lung bases links the mechanism to the target symptom rather than to a side effect.

Easy analogy or mental picture
It is checking whether the water level dropped, not whether the pump made noise. The picture separates the intended result from other changes and does not dismiss monitoring for side effects.

Memory hook
Judge a diuretic by the fluid it moved and the lungs it cleared.

NCLEX decision rule
Evaluate a medication against the problem it was prescribed for. Changes that are expected adverse effects, or values that did not move, do not demonstrate therapeutic response.

Why the other choices are wrong
A falling pressure and a falling potassium are real consequences of diuresis but are adverse effects to monitor. A weight that has not changed argues that fluid has not been removed.