Estimate an hourly maintenance-fluid rate using the weight-based 4–2–1 rule.
Maintenance Fluids Calculation
Form
Results
Maintenance fluids
$0.00
Maintenance fluids x 1.5
$0.00
Fluid bolus (20 mL/kg)
$0.00
Table of Contents
1
What is Maintenance Fluids?
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How to Use This Calculator
- Enter or select Weight.
- Check the unit beside each measurement. For a percentage or rate, use the scale and time period stated in the form.
- Choose Calculate, then compare the output with the formula and example below. If you change a value or option, calculate again to update the result.
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Formula Used
First 10 kg: 4 mL/kg/h; next 10 kg: 2 mL/kg/h; each kg above 20: 1 mL/kg/h.
4
Variables Explained
| Input | What it means |
|---|---|
| Weight | Measured mass in the chosen unit; pounds and kilograms are not numerically interchangeable. |
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Worked Example
At 25 kg, the hourly estimate is 40+20+5=65 mL/h.
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Why Use This Calculator?
Use the calculation to make the method and its inputs easier to check with a healthcare professional. Its meaning depends on the clinical setting and on whether the underlying method is appropriate for that person.
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Common Mistakes
- Maintenance, resuscitation and replacement are different tasks; illness can make this rule inappropriate.
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Frequently Asked Questions
Is this result a diagnosis or treatment instruction?
No. It describes a calculation or score from the supplied information. A qualified clinician must check the measurements, the method’s applicability and the wider clinical picture.
Can I enter the units from any lab report?
Use the units specified in the form and select a conversion only where the page provides one. Different substances need different conversion factors; a mismatch can produce a plausible but incorrect result.
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Sources & References
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