Parenteral Nutrition Flashcards
When solely on PN how fast can essential fatty acid deficiency occur
2-4 weeks without linoleic or alpha linolenic acid
Symptoms of essential fatty acid deficiency
Dry scaly rash, impaired wound healing, increased infection risk, immune dysfunction, alopecia
The Holman Index
Triene to Tetraene ratio to test for essential fatty acid deficiency
EFAD can develop faster in lipid free PN secondary to
Insulin levels in PN are increased as there is typically a high dextrose dose which prevents lipolysis of adipose tissue which would be the fail safe for releasing EFAs that would be stored
TPN in the critical care unit should initially be
hypocaloric and lipid free
Should PN be started in the acute phase of severe sepsis with elevated triglycerides
No
Alpha Linolenic Acid is the precursor for
DHA and EPA (omega 3 fatty acids)
Contents of the Injectable Lipid Emulsion (ILE)
An oil in water emulsion, 1 triglyceride, glycerol and phospholipid emulsifier, vitamin E, K phytosterols and cholesterols
Which vitamins are in ILE’s
vitamin E and K
Long chain fatty acids require ____ to be oxidized for energy
L-Carnitine
What are needed to prevent essential fatty acid deficiency?
alpha linolenic acid and linoleic acid (Omega 3’s)
What percentage of calories is needed of alpha linolenic acid to prevent EFAD
0.25-0.5% omega 3 (alpha linolenic acid)
What percentage of calories is needed of linoleic acid to prevent EFAD?
1-4% omega 6 (linoleic acid)
In which type of oils are the highest concentration of linoleic acid found
Soybean and Corn Oil (Omega 6)
In which type of oils are the highest concentration of alpha linolenic acids found in?
Soybean and Canola Oil (Omega 3)
How much ILE is needed weekly to prevent EFAD
500mL/week
Maximum PN ILE infusion daily
2.5 g/kg/day
If a patient is critically ill, don’t exceed ____ amount of lipids IV a day
1g/kg/day
When using 100% soybean oil IV, hold lipids x _____ unless there is a concern for EFAD, then give _____
For 1 week, OR
100grams/week
Give IVFE at no more than _____ rate to avoid toxicity of rapid infusion (fat overload syndrome)
0.11 g/kg/hr
Why does PPF (10% ILE) lead to hypertriglyceridemia
10% ILE’s contain lipoprotein X which competes with triglycerides for lipoprotein lipase which is responsible for the breakdown of TCG’s, therefore they build up and cause hypertriglyceridemia
What should happen if serum triglycerides exceed 400mg/dL
- Decrease fat emulsion or hold
- Monitor serum TCGs 2x/week
- Remove lipids if also on PPF
- Try to start a patient on trophic enteral feeding
Omega 9 fatty acids
Olive Oil/Oleic acid used to lower cholesterol and triglycerides without lipid peroxidation often used in EN formulas
What is the suspected role of omega 3 fatty acids in parenteral nutrition
it contains fish oil which may cause LESS inflammation. Limited evidence is available at this time to be recommended.