A nurse is caring for a client who is 3 hr postoperative and exhibiting signs of hypovolemia. Which finding indicates hypovolemia?

Rationale: A. Distended neck veins: Distended neck veins are typically associated with fluid volume excess, such as in heart failure or hypervolemia. In hypovolemia, the central venous pressure is low, often resulting in flat or collapsed neck veins due to the decreased circulating blood volume and reduced venous return. B. Rapid pulse rate: Tachycardia is a key early sign of hypovolemia, as the heart attempts to compensate for decreased blood volume by increasing the heart rate to maintain adequate cardiac output. This compensatory mechanism helps preserve perfusion to vital organs during volume loss. C. Urine output 45 mL/hr: A urine output of 45 mL/hr is considered adequate and within the normal range for an adult. In hypovolemia, renal perfusion typically decreases, often leading to oliguria (urine output less than 30 mL/hr), which would be a more specific indicator of fluid deficit. D. Decreased respiratory rate: Hypovolemia generally triggers an increase in respiratory rate (tachypnea) as a compensatory response to improve oxygen delivery and perfusion. A decreased respiratory rate would be unusual and not characteristic of a volume-depleted state.