Parenteral Nutrition Flashcards
When is parenteral nutrition needed? How many days of not being able to get adequate nutrition via GI tract?
> 5 days may be indicated
Bowel obstruction, ileus, severe diarrhea, untreatable malabsorption
What do 2 in 1 formulation contain?
2 macros
Dextrose and amino acids and lipids are infused separately if needed
Total energy expenditure (TEE) equation
TEE = BEE x activity factor x stress factor
How many calories/g are in fat, protein, and carbs?
carbs and protein 4 kcal/g
fat 9 kcal/g
What is the protein requirement for patients?
Ambulatory 0.8-1 g/kg/day
Hospitilized 1.2-2 g/kg/day
How many grams of protein in a gram of nitrogen? what is the formula?
1g of nitrogen = 6.25 g protein
Nitgoren intake = grams of protein intake / 6.25
What is the non-protein calorie to nitrogen ratio? How do you calculate it? What does it mean?
Calculate grams of nitrogen supplied per day and then divide the total non-protein calories (dextrose + lipids) by the grams of nitrogen
NPC:N ratios:
80: 1 most severely stressed
100: 1 severely stressed
150: 1 unstressed patient
Dextrose kcal/g ?
3.4 kcal/g
How much kcal/mL does 10% injectable lipid emulsion (ILE) provide? 20%? 30%?
10% ILE provides 1.1 kcal/mL
20% 2 kcal/mL
30% 3 kcal/mL
What size filter do you need for lipid emulsions for PN?
1.2 micron filters for lipids (0.22 micron will not work)
PN requires filters itself due to risk of precipitate
How to avoid Ca/P precipitate? Which do you add first to PN? What is better calcium gluconate or calcium chloride?
Calcium gluconate is less reactive and has a lower risk for precipitation
Add phosphate first (after dextrose and amino acids), followed by all other PN components, agitate the solution, then add calcium near the end
Refrigerate (higher temp more dissociate and precipitation risk increases)
Maintain proper pH (lower pH, lower risk for precipitation)
Ca and P added together shouldn’t exceed 45 mEq/L
What type of insulin do you add in PNs?
Regular insulin can be added
What is the general rule with enteral feeding and drug interactions?
Hold the feedings 1 hour before or 2 hours after the drug is administerred
What are some common drugs that interact with nutrients in feeds?
warfarin: many enteral products bind warfarin leading to low INR
Tetracyclines, quinolones, levothyroxine: will chelate with metals, including calcium, magnesium, and iron, which reduces drug
Ciprofloxacin: oral suspension NOT used with tube feeds cuz the oil-based suspension adheres to the tubes. Crush immediate release tables instead
Phenytoin: Levels are reduced when drug binds to the feeding solution, leading to less free drug availability and sub-therapeutic levels. Sep by 2 hours from feed
