How can diuretic therapy influence renal function in HF patients?

• A. Diuretics have no effect on renal function.
• B. Overdiuresis can cause dehydration and prerenal azotemia; monitor creatinine and urine output.
• C. Diuretics always improve kidney function.
• D. Renal function only worsens with fluid overload.

Answer: (B)

Diuretic therapy in heart failure must balance removing excess fluid with preserving adequate renal perfusion. When congestion is reduced, renal blood flow can improve and kidney function may get better. However, pushing diuresis too far can cut intravascular volume, decrease renal perfusion, and lead to prerenal azotemia. That’s why close monitoring is essential: track urine output and check creatinine (and often BUN) to detect a drop in kidney filtration early. If creatinine rises or urine output falls, adjust the diuretic dose or regimen to avoid further renal injury. In short, diuretics can help kidneys when they relieve congestion, but overdiuresis can impair renal function, making vigilant monitoring crucial.