What it does
Finds the maintenance IV fluid rate and 24-hour volume for a child by weight, using the Holliday-Segar method.
The rule
Hourly (4-2-1): 4 mL/kg/hr for the first 10 kg, 2 mL/kg/hr for the next 10 kg and 1 mL/kg/hr above 20 kg. The separate daily (100-50-20) estimate uses 100, 50 and 20 mL/kg/day in those weight bands. These are separate approximations, not exact hourly-to-daily conversions.
Worked example
An 18 kg child: (4 × 10) + (2 × 8) = 56 mL/hr; daily 1000 + 400 = 1400 mL/day.
Good to know
This study calculation does not select a fluid type or account for resuscitation, existing deficits or ongoing losses.
Study calculations only, not dosing recommendations. Real medication orders and administration require the appropriate clinical checks and facility protocol.
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