Maintenance Fluids Calculator
Calculate pediatric maintenance fluids using Holliday-Segar method and 4-2-1 rule
Calculate Pediatric Maintenance Fluids
Enter child's weight (minimum 3 kg for accurate calculations)
Age helps provide age-appropriate clinical context
D5NS is commonly used for pediatric maintenance fluids
Maintenance Fluid Requirements
Example Calculation
14 kg Child Example
Patient: 14 kg pediatric patient
Method: Holliday-Segar + 4-2-1 rule
Step-by-Step Calculation
Daily (24h): First 10 kg × 100 ml + Next 4 kg × 50 ml = 1000 + 200 = 1200 ml/24h
Hourly: First 10 kg × 4 ml + Next 4 kg × 2 ml = 40 + 8 = 48 ml/h
Fluid Bolus: 14 kg × 20 ml = 280 ml
Calculation Methods
Holliday-Segar Method
Daily fluid requirements (24h)
- • First 10 kg: 100 ml/kg/24h
- • Next 10 kg: 50 ml/kg/24h
- • Above 20 kg: 20 ml/kg/24h
4-2-1 Rule
Hourly flow rate
- • First 10 kg: 4 ml/kg/h
- • Next 10 kg: 2 ml/kg/h
- • Above 20 kg: 1 ml/kg/h
Clinical Guidelines
Not suitable for newborns <14 days old
Minimum weight requirement: 3 kg
Consider ideal body weight in obese patients
Monitor electrolyte balance regularly
Adjust for clinical condition and losses
Fluid Bolus
Emergency Use
For hypovolemic shock treatment
Formula: Weight (kg) × 20 ml
Maximum: 1000 ml (1 liter)
Administration: As fast as possible
Purpose: Rapid vascular volume expansion
Quick Reference
| Weight | Daily | Hourly |
|---|---|---|
| 5 kg | 500 ml | 20 ml/h |
| 10 kg | 1000 ml | 40 ml/h |
| 15 kg | 1250 ml | 52 ml/h |
| 20 kg | 1500 ml | 60 ml/h |
| 25 kg | 1600 ml | 65 ml/h |
| 30 kg | 1700 ml | 70 ml/h |
Monitoring Parameters
Frequently Asked Questions
What is the Holliday-Segar method?
The Holliday-Segar method is a well-established formula developed in 1957 by pediatricians Malcolm Holliday and William Segar. It calculates maintenance fluid requirements based on body weight using a tiered approach:
- First 10 kg: 100 ml/kg per day
- Next 10 kg (11-20 kg): 50 ml/kg per day
- Above 20 kg: 20 ml/kg per day
This method is widely used in pediatric medicine and provides a standardized approach to fluid management.
What is the 4-2-1 rule?
The 4-2-1 rule is a quick method to calculate hourly maintenance fluid rates:
- 4 ml/kg/hour for the first 10 kg
- 2 ml/kg/hour for the next 10 kg (11-20 kg)
- 1 ml/kg/hour for each kg above 20 kg
This rule is equivalent to the Holliday-Segar method but provides an easier calculation for hourly IV drip rates.
When should maintenance fluids be used?
Maintenance intravenous fluids (MIVF) are indicated when patients cannot maintain adequate hydration through oral intake:
- Post-operative patients (NPO status)
- Severe vomiting or diarrhea
- Bowel obstruction requiring bowel rest
- Critical illness preventing oral intake
- Decreased consciousness or swallowing difficulty
- Major surgery requiring NPO periods
What IV fluid types are commonly used?
Common IV fluids for pediatric maintenance include:
- D5NS: 5% Dextrose + Normal Saline (most common for pediatrics)
- D5 1/2NS: 5% Dextrose + Half Normal Saline
- D5W: 5% Dextrose in Water
- NS: Normal Saline 0.9%
- LR: Lactated Ringer's Solution
D5NS provides glucose for energy while maintaining electrolyte balance, making it ideal for most pediatric patients.
What is a fluid bolus and when is it used?
A fluid bolus is a rapid administration of IV fluids to treat acute hypovolemia or shock. The standard pediatric bolus is calculated as:
Weight (kg) × 20 ml (maximum 1000 ml)
Fluid boluses are used for:
- Hypovolemic shock
- Severe dehydration
- Septic shock
- Acute blood loss
They should be administered as rapidly as possible (usually over 10-20 minutes) and may be repeated based on patient response.
Are there any limitations to this calculator?
Yes, this calculator has several limitations:
- Not suitable for newborns under 14 days old
- Minimum weight requirement: 3 kg
- Should not be used as sole fluid therapy in critical illness
- Requires adjustment for ongoing losses (vomiting, diarrhea, fever)
- May need modification in obese patients (use ideal body weight)
- Should be adjusted based on clinical condition and electrolyte monitoring
- Not suitable for patients with renal dysfunction or heart failure
Always consult with a healthcare professional before administering fluids.
How do I adjust for additional fluid losses?
Maintenance fluids should be adjusted for ongoing losses:
- Fever: Add 10-15% per degree above 38°C
- Vomiting/Diarrhea: Replace ml-for-ml or add 25-50 ml/kg/day
- Sweating: Add 10-25 ml/kg/day in hot climates
- Respiratory losses: Add 25-50 ml/kg/day with tachypnea
- Burns: Use specialized fluid resuscitation formulas
Use the "Advanced Options" section in this calculator to add additional ongoing losses to your fluid calculation.
Understanding Pediatric Maintenance Fluids
What are Maintenance Fluids?
Maintenance intravenous fluids (MIVF) are the continuous delivery of fluids through an IV line to maintain optimal hydration and electrolyte balance when patients cannot meet their fluid requirements through oral intake alone. These fluids replace insensible losses from respiration, perspiration, and normal physiological processes.
When are they Used?
- •Post-operative patients who cannot take oral fluids
- •Children with severe dehydration or vomiting
- •Patients requiring bowel rest
- •Critical illness preventing oral intake
- •NPO (nothing by mouth) status before procedures
- •Decreased consciousness or swallowing difficulty
Physiological Basis
The Holliday-Segar method is based on caloric expenditure:
- •100 ml of water needed per 100 kcal metabolized
- •Smaller children have higher metabolic rates per kg
- •Fluid requirements decrease proportionally with weight
Historical Background
The Holliday-Segar method was developed by pediatricians Malcolm Holliday and William Segar in 1957. This well-established method assumes that a fixed amount of fluid is needed for every kilogram of body weight per day. It has been the gold standard in pediatric fluid management for over 65 years and is taught in medical schools worldwide.
Common IV Fluid Types
Provides glucose without electrolytes
Most common for pediatric maintenance
Lower sodium concentration option
For volume expansion without glucose
Balanced crystalloid with lactate buffer
Clinical Pearl: D5NS is commonly used in pediatric care to provide glucose for energy while maintaining fluid and electrolyte balance. The 5% dextrose helps prevent hypoglycemia in children who are NPO.
Electrolyte Considerations
Maintenance fluids should provide:
- • Sodium: 2-4 mEq/kg/day
- • Potassium: 1-2 mEq/kg/day (after urine output established)
- • Chloride: 2-3 mEq/kg/day
- • Glucose: 5-10 g/kg/day to prevent catabolism
Evidence-Based
The Holliday-Segar method is supported by decades of clinical research and remains the standard approach in pediatric hospitals worldwide.
Quick & Accurate
Get instant calculations for daily requirements, hourly rates, and emergency bolus volumes in seconds with our user-friendly interface.
Professional Tool
Designed for healthcare professionals including pediatricians, nurses, medical students, and emergency medicine practitioners.
Important Medical Disclaimer
This calculator is for educational and informational purposes only. It should not replace clinical judgment or professional medical advice. Always consult with qualified healthcare professionals for patient care decisions. Before administering any fluid, blood, or treatment, ensure you know the correct dose and method. The Holliday-Segar method has limitations and should not be used for newborns under 14 days old or children under 3 kg. Always consider the patient's clinical condition, ongoing losses, and individual needs when prescribing fluids.
Holliday-Segar vs 4-2-1 Rule Comparison
| Weight Range | Holliday-Segar (ml/kg/24h) | 4-2-1 Rule (ml/kg/h) | Example (15 kg child) |
|---|---|---|---|
| First 10 kg | 100 ml/kg/24h | 4 ml/kg/h | 10 kg × 100 = 1000 ml/24h 10 kg × 4 = 40 ml/h |
| Next 10 kg (11-20 kg) | 50 ml/kg/24h | 2 ml/kg/h | 5 kg × 50 = 250 ml/24h 5 kg × 2 = 10 ml/h |
| Above 20 kg | 20 ml/kg/24h | 1 ml/kg/h | N/A (child is 15 kg) |
| Total for 15 kg | 1250 ml/24h | 52 ml/h | 1250 ml/24h ÷ 24 = 52 ml/h |
Note: Both methods yield equivalent results. The Holliday-Segar method calculates daily requirements, while the 4-2-1 rule provides hourly rates for easier IV drip programming.
Common Clinical Scenarios
Post-Operative Care
Scenario: 8 kg child post-appendectomy, NPO for 24 hours
Calculation: 8 kg × 100 ml/kg = 800 ml/24h
Hourly rate: 8 kg × 4 ml/kg = 32 ml/h
Fluid type: D5 1/2NS with 20 mEq KCl/L (after voiding)
Gastroenteritis with Dehydration
Scenario: 12 kg child with vomiting and mild dehydration
Maintenance: (10×100) + (2×50) = 1100 ml/24h
Plus ongoing losses: Add 50-100 ml/kg for diarrhea
Fluid type: NS or LR for initial resuscitation, then D5 1/2NS
Fever Management
Scenario: 20 kg child with fever (39.5°C) and decreased oral intake
Base maintenance: (10×100) + (10×50) = 1500 ml/24h
Fever adjustment: +12% for 1.5°C above 38°C = +180 ml
Total: 1680 ml/24h = 70 ml/h
Emergency Resuscitation
Scenario: 15 kg child in hypovolemic shock
Fluid bolus: 15 kg × 20 ml = 300 ml NS or LR
Administration: As fast as possible (10-20 min)
Reassess: May repeat up to 60 ml/kg if needed
Then maintenance: 1250 ml/24h = 52 ml/h
⚠️ Key Clinical Considerations
When to Adjust Maintenance Fluids:
- ▸Fever: Increase by 12% per degree Celsius above 38°C
- ▸Hyperventilation: Add 25-50 ml/kg/day for increased respiratory losses
- ▸Phototherapy: Increase by 20-25% in neonates under phototherapy
- ▸Radiant warmers: Increase by 40-50% for neonates
- ▸Humid environment: May decrease requirements by 10-20%
Contraindications & Cautions:
- ✗Renal failure: Reduce fluid volume significantly
- ✗Heart failure: Restrict fluids, monitor closely
- ✗SIADH: Fluid restriction may be needed
- ✗Newborns <14 days: Use different formulas
- ✗Obesity: Calculate using ideal body weight
- ✗Cerebral edema risk: Consider hypertonic saline
Clinical Pearl: Always monitor electrolytes, urine output, and weight daily. Adjust fluids based on clinical status, not just calculations. The Holliday-Segar method provides a starting point, but individual patient factors should guide ongoing management.
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