NREMT Paramedic Practice

What does a sunken fontanelle suggest in infants?

1. Dehydration

2. Allergy to formula

3. Normal development

4. Overhydration

The correct answer is: Dehydration

A sunken fontanelle in infants is indeed indicative of dehydration. The fontanelles, or soft spots on an infant's skull, are areas where the bones have not yet fused together. These spaces are filled with fluid and help accommodate the growing brain. When an infant is dehydrated, the body prioritizes allocating fluid for vital functions, leading to a depletion of the fluid that normally keeps the fontanelle elevated and filled. In conditions of dehydration, you might also observe other signs such as decreased urine output, dry mucous membranes, irritability, or lethargy. Monitoring the fontanelle is a critical part of assessing an infant’s hydration status, as it can provide vital clues to underlying issues, allowing for timely intervention. Other options, while related to infant health, do not directly correlate with the indication provided by a sunken fontanelle. Allergies might present with various gastrointestinal or dermatological symptoms but wouldn't impact the state of a fontanelle. Normal development would typically be associated with flat or slightly elevated fontanelles during appropriate growth phases. Overhydration could potentially lead to other complications, such as bulging of the fontanelle rather than a sunken appearance.