A nurse in a clinic is assessing an infant who has diarrhea, is lethargic, and has dry skin. Which of the following findings indicates moderate dehydration?

The assessment involves grading the severity of dehydration in an infant based on clinical manifestations. Knowledge of hemodynamic markers, skin turgor, and fluid volume deficits is applied to differentiate between mild, moderate, and severe stages of dehydration. Choice A rationale . In moderate dehydration, the respiratory rate usually increases (tachypnea) as a compensatory mechanism for metabolic acidosis. A decreased respiratory rate is not a sign of dehydration but might indicate neurological depression or severe exhaustion in later stages. Choice B rationale . A bulging anterior fontanel is a clinical sign of increased intracranial pressure or overhydration. In dehydration, the fontanel is typically depressed or sunken due to the significant loss of interstitial fluid and decreased overall volume. Choice C rationale . Capillary refill of 3 seconds is a classic sign of moderate dehydration, indicating decreased peripheral perfusion. The normal range is less than 2 seconds. This delay reflects the body's attempt to shunt blood to vital organs. Choice D rationale . Mottled skin and cold extremities are signs of severe dehydration and impending circulatory collapse or shock. Moderate dehydration usually presents with dry mucous membranes and decreased turgor, whereas mottling indicates a much more critical physiological state.