Which method is commonly used to estimate maintenance IV fluids in pediatric patients?

• A. Parkland formula
• B. Holliday-Segar method
• C. Weight-based ml/kg/day only
• D. Fluid input from thirst

Answer: (B)

Pediatric maintenance IV fluids are estimated using the Holliday-Segar method, which links daily fluid needs to weight in a tiered way. This approach acknowledges that younger, lighter children have different baseline needs than heavier children, and it provides a simple, standardized way to calculate maintenance.

The method uses three weight bands:

• For the first 10 kg: 100 mL per kg per day

• For the next 10 kg (up to 20 kg): 50 mL per kg per day

• For any weight above 20 kg: 20 mL per kg per day

Add these up to get the total mL per day, then divide by 24 to convert to an hourly IV rate.

Example: a child weighing 12 kg

• First 10 kg: 10 × 100 = 1000 mL/day

• Next 2 kg: 2 × 50 = 100 mL/day

• Total: 1100 mL/day → about 46 mL/hour

Example: a child weighing 25 kg

• First 10 kg: 1000 mL/day

• Next 10 kg: 500 mL/day

• Remaining 5 kg: 5 × 20 = 100 mL/day

• Total: 1600 mL/day → about 66.7 mL/hour

Why this method is preferred: it provides a reliable, weight-based maintenance rate that reflects metabolic needs across a range of pediatric ages and sizes, ensuring proper baseline hydration and electrolyte balance.

Parkland formula is for burn resuscitation and not used for routine maintenance in children, and simply using a flat weight-based ml/kg/day without the tiered structure misses how daily needs scale with weight. Relying on thirst for IV maintenance is inappropriate because IV maintenance aims to meet ongoing requirements regardless of voluntary intake.