Which population is the Holliday-Segar method not suitable for?

• A. Neonates < 14 days old
• B. Infants older than 6 months
• C. Adults
• D. Children over 12 years

Answer: (A)

The main idea tested is who maintenance fluid estimates like the Holliday-Segar method are appropriate for. This rule is a simple, weight-based way to estimate daily maintenance fluids in pediatric patients with relatively normal kidney function: roughly 100 mL/kg/day for the first 10 kg, then 50 mL/kg/day for the next 10 kg, and 20 mL/kg/day for each kg above that, with adjustments for losses or fever. It works well for most healthy children and older infants.

But neonates in the first days of life have very different physiology. Their kidneys are immature, they have a higher surface-area-to-weight ratio, and they lose more fluid insensibly. Their total body water and electrolyte needs change rapidly after birth, so applying the standard Holliday-Segar maintenance amounts can easily misestimate their true needs, risking dehydration or fluid overload and electrolyte imbalances. Because of this, the method isn’t suitable for neonates younger than about two weeks.

For these very young patients, clinicians tailor fluids more precisely—often using isotonic solutions with carefully adjusted electrolytes and close monitoring—rather than relying on the generic pediatric maintenance formula. In contrast, the Holliday-Segar method is more appropriate for older infants, children, and, with different guidelines, for pediatric-adult transitions, while adults require different maintenance calculations.