What sign indicates that a child may be experiencing dehydration?

Decreased urinary output is a significant indicator that a child may be experiencing dehydration. In a healthy child, urine production is closely linked to fluid intake; when a child is dehydrated, the body conserves water by reducing the amount of urine produced. This reduced output serves as a physiological response to maintain fluid balance.

Other signs of dehydration, while relevant, do not directly point to the body’s ability to conserve fluids as effectively as decreased urinary output. Increased thirst is a common response that occurs as the body signals the need for more fluids but is not as definitive on its own. Dry skin can be a symptom of dehydration, but skin condition can also be influenced by factors such as the environment or individual skin types. A headache may occur due to a variety of reasons, including dehydration, but it is less specific as an indicator of fluid status. Thus, decreased urinary output is a clear and direct sign that can signal dehydration in a child, making it the most appropriate choice in this context.