Calculating Calories Provided by Nutrition

Enteral formula feeds

  1. Calculate total intake (e.g. ml’s per hour x 24). This gives you total mLs.
  2. Divide total intake by 30 mL’s per ounce. This gives you total ounces in.
  3. Multiply total ounces in by number of calories per ounce. Infant formulas are usually 20 kcal/oz, but these are often fortified to 22, 24, or 30 kcal/oz. This gives you total calories per day.
  4. Divide by weight in kg. This gives you kcal/kg/day.

Example:

4.5 kg infant receiving 28 ml/hr of 24 kcal/oz Similac by ND tube.

28 ml/hr x 24 hrs / 30 ml/oz x 24 kcal/oz / 4.5 kg = 120 kcal/kg/day

TPN and Lipids

% w/v (g/100 mL) Kcal/mL
Glucose (3.4 kcal/g) 5.0 0.17
7.5 0.26
10.0 0.34
12.5 0.425
15.0 0.51
20.0 0.68
25.0 0.85
Lipids 20.0 2.00
  1. Glucose (3.4 kcal/g)
    1. Using the table above, determine the kcal/mL in the TPN solution you are using.
    2. Multiply kcal/mL of TPN by the volume infused in 24 hours to calculate total glucose kcals.
    3. Divide total kcal per day by the patient’s weight in kg to get glucose kcal/kg/day.
  2. Protein (4 kcal/g)
    1. Multiply the g/kg/day of protein by 3.4 kcal/g to get protein kcal/kg/day.
  3. Lipids (10 kcal/g in 20% lipids)
    1. Multiply the volume of lipids in 24 hours by 2.0 Kcal/mL to get total lipid kcals.
    2. Divide total lipid kcals by the patient’s weight to get total lipid kcal/kg/day.
  4. Add kcal/kg/day provided by glucose, protein, and lipids to get total kcal/kg/day.