MNT Flashcards
In H&N cancer pts undergoing surgery, use of _ _ _ supplementation has been associated with fewer infections and shorter LOS
Arginine
ASPEN recs re: immune modulating enteral formulas containing arginine, nucleic acids, essential fatty acids
Recommends use as it may be beneficial in malnourished cancer patients undergoing major operations
Where should the catheter tip be positioned when providing PN through central venous access?
Superior vena cava or adjacent to the right atrium
Home PN patients with recurrent CRBSI despite adherence to aseptic technique should be considered for use of prophylactic:
Antimicrobial or ethanol lock solutions
Which form of calcium is preferred when compounding PN?
Calcium gluconate
Should calcium and phosphorous be added in close sequence or consecutively when compounding PN?
No
If mixed in too high a concentration, calcium and phosphorus may form an insoluble precipitate of calcium phosphate. Pulmonary emboli secondary to calcium phosphate precipitates have been the cause of at least two deaths.
What type of filter should be used for PN formulations?
1.2 micron filter may be used for all PN formulations
A 0.22 micron filter was recommended for a 2-in-1, whereas a 1.2 micron filter was recommended for TNA
PN labeling should include:
- rate and duration of infusion
- components of formulation
- beyond use date in compliance with USP <797>, ASPEN
Home PN labeling should be consistent with USP general chapter <17>:
- pt name
- drug name (spell out full generic and brand name)
- strength/dose
- purpose for use of PN should be clear “for nutrition supplementation” or “to provide nutrition”
- limit auxiliary info
What is the only form of iron that can be added to PN? What can the PN NOT contain if adding iron?
Iron dextran - required a test dose prior to initial infusion
Iron can be added when PN does not continue ILE
When should PN MVIs be added to the bag?
Immediately before starting PN infusion
How many mL should you flush an enteral tube with between medications?
15 mL water before and after each medication
Home blenderized or reconstituted powdered EN formulas should be discarded after:
24 hours
Or per manufacturer guidelines
How long should ILE - as a separate infusion - run before being discarded?
12 hours
How long can TNA hang before being discarded?
24 hours. Lipids added = altered pH which prevents microbial growth, thus allowing longer hang time
Why should amino acids not be exposed to light?
To maintain stability up to the expiration date
Adult AA solutions do not typically contain which amino acids?
Cysteine
Taurine
Glutamine
Cysteine and taurine are non-essential in adults. Cysteine can complex with copper. Copper-cysteine complexes are likely to precipitate.
Glutamine is still considered non-essential (but we know its role). The FDA has not approved glutamine in TPN, and it’s contraindicated in renal and liver disease. (Not sure what extent of disease or if dysfunction would also count)
Historically, glutamine was not added to commercial parenteral nutrition solutions due to instability.
No glutamine in AA solutions because of rapid degradation to toxic by products upon heat sterilization
The functions of glutamine are many and include:
- Regulates GI cell growth, function, and regeneration in SBS
- Conditionally essential AA during metabolic stress and injury
- Crucial for energy metabolism and proliferation of hepatocytes in the liver
- Substrate for protein synthesis
- Anabolic precursor for muscle growth
- Acid-base balance in the kidney
- Substrate for ureogenesis in the liver
- Substrate for hepatic and renal gluconeogenesis
- Oxidative fuel for intestine and cells of the immune system
- Inter-organ nitrogen transport
- Precursor for neurotransmitter synthesis
- Precursor for nucleotide and nucleic acid synthesis
- Precursor for glutathione production
Why is glutamine supplementation contraindicated in liver disease?
Conversion of glutamine to glutamate and ammonia may worsen hepatic encephalopathy
Glutamine may also diminish the therapeutic effect of lactulose
Is the aluminum contamination greater in KPhos or NaPhos?
Potassium phosphate
What two MN have the ability to reduce selenite to the poorly soluble elemental selenium?
Copper
Vitamin C
What pH value reduces risk of folic acid precipitation?
pH >5.0
What b-vitamins are are unstable in sunlight (direct or indirect)?
Thiamin
Pyridoxine
Riboflavin
What are the main determinants of thiamin degradation
Sunlight
Sulfites
