Parenteral Nutrition Formulations Flashcards
What is the smallest pore size filter that is recommended for total nutrient admixture (TNA)?
1.2 micron
According to recommendations by ASPEN parenteral nutrition safety consensus and the National Advisory Group on Standards and Practice Guidelines for parenteral formulations, the amount of dextrose used in preparation of a PN formulation is required to appear on the label as:
Grams per day (eg, dextrose 250 gm/day)
What is the most commonly used carbohydrate energy substrate in PN?
Dextrose
Amount of kcal per gram from dextrose?
3.4 kcal/gm
What concentrations is dextrose available in?
2.5-70%
Why are higher dextrose concentrations (>10%) generally reserved for central venous administration?
Because of their propensity to cause thrombophlebitis in peripheral veins
Amount of kcal per gm in glycerol (glycerin)?
4.3 kcal/gm
What is the nitrogen content of amino acid products?
Varies, but for nitrogen balance calculations, amino acid products are generally assumed to be 16% nitrogen
6.25 gm amino acid = 1 gm nitrogen
What are the most frequently used amino acid concentrations used in PN compounding?
8.5%, 10%, and 15%
What concentrations are amino acids available in?
3.5-20%
What is the theory behind modified amino acid formulations marketed for use in renal failure that are composed primarily of essential amino acids?
Theory that nonessential amino acids can be physiologically recycled from urea, whereas essential amino acids must be provided from the diet
Do essential amino acid formulations offer a significant advantage in renal failure?
No
What are the 2 ILE formulations available in the US?
Intralipid and Smoflipid
The 2 ILE formulations available in the US are composed solely of what kind of triglycerides?
Long-chain triglycerides
What are the available concentrations of commercial ILE formulations?
20% and 30%
What is the kcal content of 20% ILE concentrated formula?
2 kcal/ml
What is the kcal content of 30% ILE concentration formula?
2.9-3 kcal/ml, depending on the manufacturer
Are 10% ILE formulations available for PN?
No, currently marketed only in premixed products and products with a lipid emulsion such as Propofol.
What effect does the high phospholipid:triglyceride ratio of 10% ILE have?
Increases the presence of free phospholipids, which interfere with lipoprotein lipase activity, thereby decreasing the lipid clearance rate
Is ILE 30% formula available for direct IV administration?
No. ILE 30% formulation is approved only for the compounding of a 3-in-1 admixture (ie, TNA)
What are the major component fatty acids in the 100% soybean based ILE?
Linoleic acid, oleic acid, palmitic acid, alpha-linolenic acid, stearic acid
Do ILE products using a 50:50 mix of soybean oil and safflower oil contain more or less omega-3 fatty acids than ILE using 100% soybean oil?
Less. Safflower oil contains only a trace of alpha-linoleic acid. Contain half as much omega-3 fatty acid (alpha-linolenic acid) as 100% soybean oil ILE
What led to the development of alternative ILE formulations made from various oil sources?
Concern about the high content of proinflammatory omega-6 polyunsaturated fatty acids (PUFA) in traditional ILE
Describe the general composition of Smoflipid and the percent concentration that is available?
Smof refers to the types of oils in it: soybean oil (30%), medium-chain triglycerides (30%), olive oil (25%), and fish oil (15%). Available as a 20% solution
What is the mean essential fatty acid concentration of Smoflipid?
35 mg/mL linoleic acid
4.5 mg/mL alpha-linolenic
Compared with soybean oil-based ILE, what clinical outcomes has Smoflipid been associated with?
Reduced liver changes and the preservation of antioxidant capacity in pediatric home PN patients, adult intestinal failure long-term PN patients, and critically ill patients
What are the other components of ILE formulations (aside from oils) and their purpose?
Egg phospholipid emulsifier (contributes 15 mmol phosphate per liter)
Glycerin to render the formulation isotonic
Sodium hydroxide to adjust the final pH to a range of 6-9
What rate should the ILE infusion rate not exceed (whether infused separately from amino acids and dextrose or as a TNA)?
Should not exceed 0.11 gm/kg/hour
What are infusion rates >0.11 gm/kg/hour of ILE associated with?
Increased risk of adverse effects such as hypertriglyceridemia, infectious complications, and fat overload syndrome (headaches, seizures, fever, jaundice, hepatosplenomegaly, abdominal pain, respiratory distress, pancytopenia, shock)
The daily dose of ILE should not exceed what % of total energy requirements?
Should not exceed 60% of total energy requirements or 2.5 gm/kg/day
What are the ASPEN/SCCM guidelines regarding soybean oil-based ILE in critical illness?
Suggest clinicians either withhold soybean oil-based ILE or limit it to a maximum of 100 gm (often divided into 2 doses) during the first week following initiation of PN if the patient is at risk for EFAD
Why do many clinicians limit soybean oil-based ILE to 1 gm/kg/day
Because of higher omega-6 fatty acid provision
What is the most dramatic impact seen with the use of ILE rich in omega-3 fatty acids?
Seen in the treatment of pediatric intestinal failure associated liver disease, with more rapid and frequent cholestasis reversal with fish oil-based ILE compared to soybean oil-based ILE
What advantages do olive-oil based fat emulsions (such as Clinolipid) have?
Offer advantages over the current polyunsaturated LCT ILE, including decreased peroxidation and a lack of in vitro lymphocyte function inhibition. Found to be clinically safe and well tolerated with a tendency to preserve hepatic function
What is the preferred form of calcium for PN?
Calcium gluconate
What is the preferred form of magnesium for PN?
Magnesium sulfate
Daily parenteral requirement for sodium?
1-2 mEq/kg
Daily parenteral requirement for potassium?
1-2 mEq/kg
Daily parenteral requirements for chloride and acetate?
As needed to maintain acid-base balance
Daily parenteral requirement for calcium?
10-15 mEq
Daily parenteral requirement for magnesium?
8-20 mEq
Daily parenteral requirement for phosphate?
20-40 mmol
Commercially available parenteral sodium salts?
Acetate, chloride, phosphate, bicarbonate, lactate
Commercially available parenteral potassium salts?
Acetate, chloride, phosphate
Commercially available parenteral chloride salts?
Sodium, potassium
Commercially available parenteral calcium salts?
Gluconate, gluceptate, chloride
Commercially available parenteral acetate salts?
Sodium, potassium
Commercially available parenteral magnesium salts?
Sulfate, chloride
Commercially available parenteral phosphate salts?
Sodium, potassium
What form of sodium salt should be avoided in PN mixtures?
Bicarbonate and lactate
What form of calcium should be avoided in PN mixtures?
Calcium chloride
What are the ASPEN recommendations for reducing complications from adult trace element products?
Decrease copper to 0.3-0.5 mg/day
Decrease manganese to 55 mcg/day
Manufacturing a product with no chromium (or max of 1 mcg/day)
Including selenium in all products at a higher dose of 60-100 mcg/day
Trace element contamination in PN formulations be limited to <0.1 mg/day of copper and 40 mcg/day of manganese