What are the Signs of Dehydration in Infants?

Dehydration in infants can develop quickly in hot weather, during illness when the baby is unable to keep liquids down and/or refuses to drink. Left untreated, dehydration, can be fatal. Parents and caretakers should know the behavioral and physical signs and symptoms of both mild-to-moderate and severe dehydration in infants which include urine production, weight loss, and soft spots on the head.

Urine output is a very good indication of dehydration. Healthy, hydrated babies usually produce a wet diaper every few hours. Babies with dehydration will have decreased urine output resulting in a wet diaper no more than every four to six hours. The urine may also have a strong smell and be dark colored.

Weight loss is another symptom of dehydration in infants. A baby who has mild-to-moderate dehydration may lose 3-9% of body weight. In cases of severe dehydration, the baby's weight loss can be over 9% of body weight.

The fontanels, or soft spots, on a baby's head are ordinarily flush with the rest of the scalp. In the case of a mildly to moderately dehydrated infant, the fontanels may be slightly sunken or depressed. Deeply sunken fontanels are a sign of extreme dehydration in infants. The fontanels may also have noticeable pulsing in worst-case situations.

Babies who have mild-to-moderate dehydration may be lethargic, listless, and/or more irritable than usual. Severe dehydration in infants may also cause extreme sleepiness. Caregivers may have difficulty waking infants from sleep. In the worst cases of dehydration, the baby may become unconscious and nonresponsive.

Cool hands and feet, the production of very few tears when crying, and sticky, dry mucous membranes are other indicators of mild-to-moderate dehydration in infants. Severely dehydrated infants may also have cool hands and feet, as well as splotchy, mottled, or blue skin with parched mucous membranes. Very dehydrated babies will not produce any tears when they cry.

Heart rate may be increased and the quality of the pulse may be diminished in babies who are mildly or moderately dehydrated. In severe cases, the baby will have a rapid heart rate, and a weak, thready pulse. The pulse may even be undetectable.

In a hydrated infant, the skin returns to normal instantly if it is pinched gently. In infants with mild-to-moderate dehydration, it may take the skin up to two seconds to return to normal. The skin of dangerously dehydrated infants either stays wrinkled or takes longer than two seconds to normalize.

Pressing the fingernail of a hydrated infant will cause blanching and the nail bed turns white. Once the nail is released, the capillaries will refill instantly and color returns. The nail beds of mildly to moderately dehydrated infants also blanch, but capillary refill is prolonged. The capillary refill of a severely dehydrated infant is extremely slow or does not completely refill.

Babies can live for a few days without eating, but may die suddenly if they become severely dehydrated. Caregivers who notice any of the symptoms of dehydration should immediately get in touch with the doctor or take the baby to the emergency room of the nearest hospital. If a caregiver is unsure whether a baby is dehydrated, it is best to err on the side of caution and contact a medical professional.