Oliguria threshold is defined as urine output less than?

Oliguria threshold is defined as urine output less than?

• A. Less than 500 mL per day
• B. Less than 800 mL per day
• C. Less than 400 mL per day
• D. Less than 200 mL per day

Answer: (C)

Oliguria means the kidneys are making much less urine than normal, signaling possible volume depletion, reduced renal perfusion, or early kidney injury. In adults, the threshold most often used in practice is urine output less than 400 mL in 24 hours. Normal daily urine production is about 800–2000 mL, so dropping below 400 mL/day indicates a significant reduction in kidney function or perfusion that requires prompt evaluation and management. Anuria is a more extreme state, typically defined as urine output approaching zero (often cited as <100 mL/day).

Oliguria means the kidneys are making much less urine than normal, signaling possible volume depletion, reduced renal perfusion, or early kidney injury. In adults, the threshold most often used in practice is urine output less than 400 mL in 24 hours. Normal daily urine production is about 800–2000 mL, so dropping below 400 mL/day indicates a significant reduction in kidney function or perfusion that requires prompt evaluation and management. Anuria is a more extreme state, typically defined as urine output approaching zero (often cited as <100 mL/day).