Pediatric Maintenance IV Fluid Calculator
Results
Hourly Rate: mL/hr
Total Daily Volume: mL/day
Understanding Pediatric Maintenance IV Fluid Calculation
Calculating the correct intravenous (IV) fluid rate for pediatric patients is a critical skill in clinical settings. Unlike adults, children have different metabolic rates and body water compositions, meaning their fluid requirements change significantly as they grow. The most common standard for determining these requirements is the Holiday-Segar Method, often referred to as the "4-2-1 Rule."
The 4-2-1 Rule Explained
The 4-2-1 rule is used to calculate the hourly maintenance rate for IV fluids based on the child's weight in kilograms (kg). Here is how the calculation breaks down:
- For the first 10 kg: 4 mL per kg per hour.
- For the next 10 kg (11-20 kg): 2 mL per kg per hour.
- For every kg over 20 kg: 1 mL per kg per hour.
Calculation Example
If a child weighs 25 kg, the calculation for the hourly IV rate would look like this:
- First 10 kg: 10 kg × 4 mL/hr = 40 mL/hr
- Second 10 kg: 10 kg × 2 mL/hr = 20 mL/hr
- Remaining 5 kg: 5 kg × 1 mL/hr = 5 mL/hr
- Total Rate: 40 + 20 + 5 = 65 mL/hr
Daily Fluid Requirements (The 100/50/20 Rule)
If you need to calculate the total fluid volume over a 24-hour period, the formula follows a similar tiered approach:
- 0-10 kg: 100 mL/kg/day
- 10-20 kg: 1000 mL + 50 mL/kg for each kg over 10
- >20 kg: 1500 mL + 20 mL/kg for each kg over 20
Clinical Considerations and Safety
While the Holiday-Segar method provides a baseline for maintenance fluids, clinical judgment is always required. Certain conditions may require adjustments to these rates:
- Dehydration: Children with significant fluid loss from vomiting or diarrhea may require boluses (usually 20 mL/kg of isotonic crystalloid) in addition to maintenance.
- Renal or Cardiac Issues: Patients with heart failure or kidney disease may require fluid restriction to avoid overload.
- Electrolyte Balance: Standard maintenance fluids for children often include D5 0.45% NS (Normal Saline) or D5 0.9% NS, typically with added Potassium Chloride (KCl) depending on the patient's labs.