Oliguria is most commonly associated with which volume status?

Oliguria is most commonly associated with which volume status?

• A. Hypovolemia
• B. Euvolemia
• C. Hypervolemia
• D. Polyuria

Answer: (A)

Oliguria happens when the kidneys aren’t receiving enough blood flow, so they conserve fluid and reduce urine production. The setting that most commonly leads to this is hypovolemia—low circulating volume from dehydration, bleeding, or significant fluid losses. When intravascular volume drops, renal perfusion pressure falls and the kidneys respond by decreasing filtration and reabsorbing more sodium and water to preserve blood pressure. This reflex keeps you from losing more fluid, but it also drops urine output, often to below about 0.5 mL/kg per hour (roughly under 400–600 mL in 24 hours for many adults). If fluids are given and perfusion improves, urine output typically rises again. Euvolemia would usually maintain normal urine output, hypervolemia can produce edema and other signs of fluid overload rather than oliguria as a primary feature, and polyuria is excessive urine production, not reduced output.

Oliguria happens when the kidneys aren’t receiving enough blood flow, so they conserve fluid and reduce urine production. The setting that most commonly leads to this is hypovolemia—low circulating volume from dehydration, bleeding, or significant fluid losses. When intravascular volume drops, renal perfusion pressure falls and the kidneys respond by decreasing filtration and reabsorbing more sodium and water to preserve blood pressure. This reflex keeps you from losing more fluid, but it also drops urine output, often to below about 0.5 mL/kg per hour (roughly under 400–600 mL in 24 hours for many adults). If fluids are given and perfusion improves, urine output typically rises again. Euvolemia would usually maintain normal urine output, hypervolemia can produce edema and other signs of fluid overload rather than oliguria as a primary feature, and polyuria is excessive urine production, not reduced output.