Which findings suggest fluid volume deficit?

• A. Tachycardia, dry mucous membranes, oliguria; elevated BUN and hematocrit
• B. Hypotension with edema and polyuria
• C. Jaundice and elevated bilirubin
• D. Hyperglycemia with fruity breath

Answer: (A)

Fluid volume deficit presents as signs of reduced intravascular volume and concentrated blood constituents. Tachycardia arises as the body tries to maintain cardiac output with less circulating fluid. Dry mucous membranes reflect dehydration, while oliguria shows the kidneys conserving water in response to decreased perfusion. Laboratory values like elevated BUN and hematocrit occur because plasma volume loss concentrates the blood components (hemoconcentration).

Other patterns don’t fit deficit: edema with hypotension and polyuria suggests fluid imbalance with excess or redistribution rather than a deficit; jaundice with elevated bilirubin points to liver dysfunction; hyperglycemia with fruity breath points to diabetic ketoacidosis.