Which statement about fluid volume excess is true?

• A. Increased urine output
• B. Decreased sodium intake
• C. Low fluid intake
• D. Compromised regulatory mechanisms

Answer: (D)

Fluid volume excess happens when the systems that regulate how much water and sodium the body retains or excretes aren’t working properly. The kidneys, plus hormones like antidiuretic hormone, aldosterone, and natriuretic peptides, coordinate to keep extracellular fluid in balance. If these regulatory mechanisms are compromised, the body can’t excrete enough sodium and water, leading to an expansion of extracellular fluid and edema.

That’s why the statement describing compromised regulatory mechanisms is true. Increased urine output would counteract fluid overload, and decreased sodium intake or low fluid intake would generally reduce, not produce, fluid volume excess.