Which parameter would reflect fluid volume status?

Which parameter would reflect fluid volume status?

• A. Urinary output
• B. EKG rhythm
• C. Nail bed color
• D. Temperature

Answer: (A)

Fluid volume status is most directly reflected by urine output because the kidneys adjust urine formation in response to circulating volume and perfusion. When effective arterial volume falls, renal perfusion drops and mechanisms like ADH and the renin-angiotensin system conserve water and salt, reducing urine output. When volume is sufficient or excess, the kidneys excrete more fluid, increasing urine output. In adults, a typical baseline is about 0.5 mL/kg/hour, and sustained changes clues you in to shifts in volume status, assuming normal kidney function and no diuretics. Other options don’t measure volume directly: EKG rhythm shows heart electrical activity, not fluid quantity; nail bed color reflects perfusion and oxygen delivery with many influencing factors; temperature indicates metabolic state or infection, not fluid load.