Oliguria is defined as which of the following?

Oliguria is defined as which of the following?

• A. Increased urine output
• B. Decreased urine output
• C. Normal urine output
• D. No urine output

Answer: (B)

Oliguria means the kidneys are producing less urine than normal. In adults this is typically defined as urine output under 0.5 mL per kilogram per hour, about 400–500 mL over 24 hours. This is different from polyuria, where output is increased, and from normal urine output or from anuria, which is no urine at all. Oliguria can point to reduced kidney perfusion or early kidney injury—causes like dehydration, fluid loss, shock, or obstructive problems—so it’s important to assess fluid status, blood pressure, and renal function when you see it.

Oliguria means the kidneys are producing less urine than normal. In adults this is typically defined as urine output under 0.5 mL per kilogram per hour, about 400–500 mL over 24 hours. This is different from polyuria, where output is increased, and from normal urine output or from anuria, which is no urine at all. Oliguria can point to reduced kidney perfusion or early kidney injury—causes like dehydration, fluid loss, shock, or obstructive problems—so it’s important to assess fluid status, blood pressure, and renal function when you see it.