Computation of Fluid Needs in Pediatrics
Infants and children have a greater need for water and are vulnerable to alterations in
fluid and electrolyte balance. There are various ways to calculate fluid requirements in
children. (one method not included here is using cc/m2 of body surface area)

Daily rate of pediatric maintenance IV fluids is based on mg/kg
Body Mass
Maintenance Flds/24 Hrs.
o 0 - 10 kg
100 mL per kg
o 11 - 20 kg
50 mL per kg
o over 20 kg
20 mL per kg got each kg
Example…….24 kg child
10 x 100 = 1000mL
10 x 50 = 500 mL
4 x 20 = 80 mL
1580 mL in 24 hrs.
Order is 30 mL / hour…. Is this safe?
24 hours x 30 mL = 720 mL/24 hours...yes, the order is safe
Problem….....30 kg child
Order 50 mL of D5 1/3 NS per hour
Is the order safe?

Fluid requirements calculated in cc/calories of metabolism
A child needs water to metabolize calories. In general a child needs 50-100
kcal/kg/day. The smaller the child, the larger number of calories needed
(example: premature infant may require 100-150 kcal/kg/day)

Step I : Basic calories are determined according to weight
 3-10 kg……50 kcal/kg
 10-15 kg…..45 kcal/kg
 15-20 kg…..40 kcal/kg
 20-25 kg…..35 kcal/kg
Example…….A 10 kg child needs 50 kcal x 10 kg = 500 kcal/day

Step 2 : Add an additional 8% of the daily basal calories need for each degree of
temperature over 100O F rectally
Example……This same child has 102o R
basal calories/day = 500
add 16% (8% for each degree above 100o)
500 x 0.16 = 80 calories
This child needs 580 kcal/day

Step 3 : Add from 0 to 30% of daily basal calories as an allowance for activity
Example.....Add 20% for activity
500 x .20 = 100
Total for Child:
basal calories
temperature
activity

500
80
100
680 kcal/day
Step 4 : To calculate Fluid requirements: allow 120 cc per 100 calories of
metabolism
Example…..680 calories – 100 = 6.8
120 cc x 6.8 = 816 cc/24 hrs. of maintenance fluids
In addition to maintenance requirements, a child may be receiving replacement fluids for:
 Any dehydration deficit requires an additional 100 cc/kg/day for 10% dehydration
or
 Any continuous excess losses due to persistent vomiting or diarrhea
Fluid Maintenance Calculations
 Child’s Weight
o 0 -10 kg
o 11 – 20 kg
o 20+ kg
Formula to calculate 24-hour fluid requirements
100 ml/kg
1,000 ml + 50 ml/kg for each kg over 10 kg
1,500 ml + 20 ml/kg for over 20 kg
Example…..5 kg: 5 x 100 = 500 ml/24 hrs or 21 ml/hr
15 kg: 1,000 + (5 x 50) = 1,250 ml/24 hrs or 52 ml/hrs
25 kg: 1,500 + (5 x20) = 1,600 ml/24 hrs or 67 ml/hrs