Pediatric Fluid And Output Calculation

 

A.      BODY WEIGHT METHOD (Remember to convert lbs. to kgs.) (p. 1095)

1. Daily maintenance fluid requirement formula:

0-10 kg 100 mL/kg/day (100 x kg)

11-20 kg 1000 mL (for first 10 kg) + 50 mL/kg/day for each additional kg between 10- 20 kg

over 20 kg 1500 mL (for first 20 kg) + 20 mL/kg/day for each additional kg over 20 kg

 

2. Hourly maintenance fluid requirements: Divide daily volume by 24 (hours/day)

Examples:

         Calculate the daily and hourly maintenance fluid requirements for a child weighing 5 kg.

100 mL x 5 kg = 500 mL / day

500 mL 24 hours = 20.8 mL / hr

         Calculate the daily and hourly maintenance fluid requirements for a child weighing 15 kg.

1000 mL + (50 mL X 5 kg) = 1000 + 250 = 1250 mL/day

1250 mL 24 = 52 mL / hr

 

         Calculate the daily and hourly maintenance fluid requirements for a child weighing 22 kg

1500 mL + (20 mL X 2 kg) = 1500 + 40 = 1540 mL/day

1540 mL 24 = 64 mL / hr

 

B.      BODY SURFACE AREA (BSA) METHOD

1.)          Use a nomogram to find the body surface area (BSA) in meters squared (M2). (p. 996); plot height and weight in appropriate columns, draw imaginary line between, intersection point is M2

 

2.)          Maintenance Fluids = 1500- 2000 mL/ M2/day

Fluid Restriction = 1200 1500 mL/ M2/day

 

Examples:

          Calculate the maintenance fluid requirements for a child whose BSA is 0.8 M2.

1500 mL X 0.8 = 1200 mL/day 1200 24 = 50 mL / hr

2000 mL X 0.8 = 1600 mL/day 1600 24 = 66 mL / hr

          Calculate the fluid restriction volumes for a child whose BSA is 0.8 M2.

1200 mL X 0.8 = 960 mL/day 960 24 = 40 mL / hr

1500 mL X 0.8 = 1200 mL/day 1200 24 = 50 mL / hr

 

C. OUTPUT CALCULATION

1.       Convert grams to mL (1 gram = 1 mL)

2.       Normal output: 1-3 cc/kg/hr,

3.       Divide total output volume by weight and hours

 

Example:

         Calculate the cc/kg/hr for a 5-kg infant who had the following output over the past 8 hours: 33g, 27g and 30 g diapers. Scale zeroed with dry diaper.

33 + 27 + 30 = 90 mL total 90 mL 8 hours = 11.25 mL/hr 11.25 5 kg = 2.25 mL/kg/hr

Output is within normal range