Maintenance Fluid Calculation

1.Caloric Expenditure method

This method is effective for all ages, types of body habitus, and clinical states.

-For each 100 calories metabolized in 24 hr, the average patient will need 100–120 mL H2O, 2–4 mEq Na+, and 2–3 mEq K+

-Adjust caloric expenditure needs by various factors (e.g., fever, activity)

.

Caloric Expenditure Method

AVERAGE WATER AND ELECTROLYTE REQUIREMENTS PER 100 CALORIES PER 24 HOURS

Clinical State H2O (mL) Na+ (mEq) K+ (mEq

Average patient receiving parenteral fluids[*] 100–120 2–4 2–3

Anuria 45 0 0

Acute CNS infections and inflammation 80–90 2–4 2–3

Diabetes insipidus Up to 400 Var Var

Hyperventilation 120–210 2–4 2–3

Heat stress 120–240 Var Var

High-humidity environment 80–100 2–4 2–3

Reference -Harriet lane

Maintenance Fluid Calculation

2. HOLLIDAY-SEGAR METHOD Estimates caloric expenditure in fixed weight

categories; it assumes that for each 100 calories metabolized, 100 mL of H2O will be required.

-Holliday-Segar method is not suitable for neonates < 14 days old; generally, it overestimates fluid needs in neonates compared with the caloric expenditure method

Fluid Requirements in:Infants and Children

HOLLIDAY-SEGAR METHOD

First 10kg 100ml/kg(4ml/kg/hr)

Na+3

10-20kg 1000ml + 50ml/kg for each Kg>10kg(40ml/hr+2ml/kg/hr(wt-10kg)

K+2

>20kg 1500ml +20ml/kg for each Kg>20kg(60ml/hr + 1ml/kg/hr( wt-20 kg)

Cl-2

Maintenance Fluid Calculation

3. BODY SURFACE AREA METHOD

-Based on the assumption that caloric expenditure is related to BSA

-It should not be used for children <10 kg

Body Surface Area Method

STANDARD VALUES FOR USE IN BODY SURFACE AREA METHOD

H2O 1500 mL/m2/24 hr

Na+ 30–50 mEq/m2/24 hr

K+ 20–40 mEq/m2/24 hr

Reference- Harriet lane

SAMPLE ESTIMATED ENERGY REQUIREMENTS FOR HEALTHY BOYS AND GIRLS OF MEDIAN WEIGHT AND

HEIGHT

Age Boys EER (kcal/kg/day) Girls EER (kcal/kg/day)

0–2 mo 107 104

3 mo 95 95

4–35 mo 82 82

Median Weight, Boys (kg)

sedentary[†]

(kcal/kg/d)Active[†]

(kcal/kg/d)

Median Weight, Girls (kg)

Sedentary[†]

(kcal/kg/d)Active[†]

(kcal/kg/d)

3 yr 14.3 80 104 13.9 76 100

4 yr 16.2 74 97 15.8 70 93

5 yr 18.4 68 90 17.9 65 87

6 yr 20.7 63 84 20.2 61 81

7 yr 23.1 59 80 22.8 56 75

8 yr 25.6 56 75 25.6 52 71

9 yr 28.6 53 71 29.0 48 65

10 yr 31.9 49 67 32.9 44 60

11 yr 35.9 46 63 37.2 41 56

12 yr 40.5 44 60 41.6 38 52

13 yr 45.6 42 57 45.8 36 50

14 yr 51.0 40 55 49.4 34 47

15 yr 56.3 39 54 52.0 33 45

16 yr 60.9 38 52 53.9 32 44

17 yr 64.6 36 50 55.1 31 43

18 yr 67.2 35 49 56.2 30 42

Fluid Calculation

• Fluid requirement of a 2 year old child by various methods

• 2 year old child has

Weight 50th centile= 12 kg

Height 50th Centile = 86 cm

BSA=0.534 m sq

Caloric Requirement- 82kcal/kg

Fluid Calculation

• Caloric method.

Total calorie requirement for 24 hrs- 82 x12= 984 kcal

For each 100kcal requires 100-120ml water

So 984 Kcal requires-120 x 9.84=1180 ml/24 hrs

Electrolyte requirement.

Na- 4 x 9.84 =39 Meq/24 hrs

K- 3 x 9.84 = 29 meq/24hrs

Fluid Calculation

• HOLLIDAY-SEGAR METHODFor a child with 12 kg weight will require 1100 ml of

fluid/24 hrs-for first 10 kg require 100ml/kg which is 10 x100 =1000 ml.For next 2 kg 50 ml/kg which is 2 x 50 =100Total Fluid Requirement =1100/24hrsElectolytes Requirements-Na-12 x 3= 36meq/24 hrsK-12x 2=24meq/24hrs

Fluid Calculation

• BODY SURFACE AREA METHOD

Child with 12 kg and 86 cm

BSA= 0.534

For 1 m sq 1500ml/24 hrs

So he will require 0.534 x 1500= 801 ml/24 hrs

Electrolyte Requirement:

Na-0.534 x 50= 27 meq /24 hrs

K-0.534 x 40=21meq /24 hrs