Pediatric IV Fluid Maintenance Calculator
Calculates hourly and daily fluid requirements using the Holiday-Segar (4-2-1) Method.
What is the Holiday-Segar 4-2-1 Rule?
The 4-2-1 rule is the clinical standard for calculating maintenance intravenous fluid (IVF) rates in pediatric patients. It estimates the amount of fluid required to maintain hydration in a healthy child who is unable to take oral fluids. This calculation is vital in pediatric care because children have higher metabolic rates and different surface-area-to-mass ratios compared to adults, making them more susceptible to dehydration.
The Calculation Breakdown
The formula divides the child's weight into three tiers to determine the hourly fluid rate (mL/hr):
- First 10 kg: 4 mL/kg/hr
- Next 10 kg (11-20 kg): 2 mL/kg/hr
- Each additional kg (>20 kg): 1 mL/kg/hr
– First 10 kg: 10 * 4 = 40 mL/hr
– Next 10 kg: 10 * 2 = 20 mL/hr
– Final 5 kg: 5 * 1 = 5 mL/hr
Total: 65 mL/hr
When to Use This Calculator
This pediatric IVF rate calculation is intended for maintenance therapy. It does not account for fluid boluses required for acute resuscitation, nor does it account for ongoing abnormal losses (such as vomiting, diarrhea, or chest tube drainage). Clinicians should always adjust the calculated rate based on the patient's specific clinical condition, electrolyte levels, and renal function.
Important Considerations in Pediatric Fluids
While the volume is important, the type of fluid (tonicity) is equally critical. Current guidelines often recommend isotonic solutions (like 0.9% Normal Saline) to prevent hospital-acquired hyponatremia, though historically hypotonic solutions were used. Always follow institutional protocols and consult with a senior clinician for neonates or children with complex conditions like heart failure or renal impairment.
Fluid Deficit vs. Maintenance
It is important to distinguish between maintenance and deficit replacement. Maintenance fluid replaces normal daily losses through urine, stool, skin, and lungs. If a child is dehydrated, you must calculate the Deficit separately and add it to the maintenance rate or replace it over a specific timeframe (usually 24-48 hours).