Maintenance fluid calculation

Comparison of different methods to calculate maintenance fluid

1. 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 H 2 O, 2–4 mEq Na + , and 2–3 mEq K + - Adjust caloric expenditure needs by various factors (e.g., fever, activity) .

2. Caloric Expenditure Method AVERAGE WATER AND ELECTROLYTE REQUIREMENTS PER 100 CALORIES PER 24 HOURS Clinical State H 2 O (mL) Na + (mEq) K + ( mEq Average patient receiving parenteral fluids [*] 100–120 2–4 2–3 Anuria 45 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

3. 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 H 2 O 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

4. 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

5. 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

6. Body Surface Area Method STANDARD VALUES FOR USE IN BODY SURFACE AREA METHOD H 2 O 1500 mL/m 2 /24 hr Na + 30–50 mEq/m 2 /24 hr K + 20–40 mEq /m 2 /24 hr Reference- Harriet lane

7. 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

8. 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

9. Fluid Calculation Fluid requirement of a 2 year old child by various methods 2 year old child has Weight 50 th centile= 12 kg Height 50 th Centile = 86 cm BSA=0.534 m sq Caloric Requirement- 82kcal/kg

10. 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

11. Fluid Calculation HOLLIDAY-SEGAR METHOD For 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 =100 Total Fluid Requirement =1100/24hrs Electolytes Requirements- Na-12 x 3= 36meq/24 hrs K-12x 2=24meq/24hrs

12. 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