Nutrition calculations Flashcards
Dietary carbohydrate and enteral nutirion carbs = x kcal
4 kcal/gram
Dextrose in PN has 3.4 kcal/gram
Glycerol in PN has 4.3 kcal/gram (not used often)
Fats = x kcal/g
9 kcal/gram
10% fat emulsion = 1.1 kcal/mL
20 % = 2 kcal/mL
30 % = 3 kcal/mL
Protein = x kcal/g
4 kcal/mL
Indications for PN
bowel obstruction
ileus
severe diarrhea
malabsorption
Equation for determining fluid needs
Pts > 20 kg:
1500 mL + (20 ml) (wt - 20 kg)
General guideline:
30-40 ml/kg/day
Basal Energy Expenditure (BEE) equation estimation
15 - 25 kcal/kg (adults)
Total Energy expenditiure (TEE) equation
BEE x activity factor x stress factor
Calculating protein needs
- 8-1 g/kg/day (ambulatory, non-hospitalized)
1. 2-2 g/kg/ day (Hospitalized, malnourished)
Which element is release from protein catabolism?
Nitrogen
1 gram of Nitrogen for each 6.25 g of protein
Nitrogen intake = g of protein intake/ 6.25
Usual proportion of non-protein calories in PN
70 - 85% of carbs
15 - 30 % of fats
What size filter is used for lipid emulsions?
1.2 micron filters
The major extracellular cation
Sodium
23.4 % sodium chloride = 4 mEq/mL
Sodium acetate is preferred in PN if pt is acidotic
The major intracellular cation
potassium
Corrected calcium
when albumin is less than 3.5
= serum calcium + [(4.0 - albumin) x 0.8]
Rules for adding Ca and Phos to PN
Ca and Phos can bind together and form precipatates
Use calcium gluconate
add Phos first, add calcium at the end
keep mixed bag in fridge until ready for admin
do not exceed a total of 45 mEq/L
Fat soluble vitamins in PN mixture [4]
Vit A, D, E K (some mixtures do not have Vit K- MVI-12)
Water soluble vitamins in PN mixture [9]
thiamine (b1), riboflavin (b2), niacin (b3), pantothenic acid, pyridoxine (b6), asocrbic acid (vit C), folic acid (b9), cyancobalamin (b12), biotin
Trace elements used in PN
zinc copper chromium manganese selenium
General rule for separating drugs and enteral feedings
hold feeding 1 hr before and 2 hrs after the drug
some drugs might require further separation
Specific drug-nutrient interactions with tube feedings
Warfarin: feedings can bind to drug and lower INR
TetracyclineL chelates with Ca, Mg, etc
Cipro: Cipro suspension cannot be used bc it adheres to the feeding tube; crush up IR tabs and mix with water
Phenytoin suspension: binds to feedings, leads to decr drug levels
