CSPT CSPT - Compounded Sterile Preparation Technician Parenteral Nutrition and IV Admixture Preparation Questions and Answers 4 — Questions and Answers
Question 1: Which electrolyte is most critical to monitor in patients receiving long-term total parenteral nutrition (TPN) due to the risk of refeeding syndrome?
- Sodium
- Phosphate (Correct answer)
- Calcium
- Chloride
Correct answer: Phosphate
Phosphate drops precipitously during refeeding syndrome as cells take up phosphate rapidly during anabolism, making it the most critical electrolyte to monitor.
Question 2: When preparing a TPN admixture, dextrose is added before lipid emulsion in a 3-in-1 (total nutrient admixture) primarily to:
- Reduce microbial contamination risk
- Maintain appropriate pH to stabilize the emulsion (Correct answer)
- Prevent calcium-phosphate precipitation
- Decrease the osmolarity of the final product
Correct answer: Maintain appropriate pH to stabilize the emulsion
Adding dextrose before lipid emulsion helps maintain an appropriate pH environment that stabilizes the lipid emulsion and prevents cracking.
Question 3: A pharmacist requests 500 mL of a 0.45% NaCl solution. You have 1 L bags of 0.9% NaCl and SWFI. How much 0.9% NaCl and SWFI are needed?
- 250 mL NaCl + 250 mL SWFI (Correct answer)
- 333 mL NaCl + 167 mL SWFI
- 400 mL NaCl + 100 mL SWFI
- 167 mL NaCl + 333 mL SWFI
Correct answer: 250 mL NaCl + 250 mL SWFI
Using the dilution equation C1V1=C2V2: (0.9%)(V1) = (0.45%)(500 mL), so V1 = 250 mL of 0.9% NaCl and 250 mL of SWFI.
Question 4: Which component of a TPN formulation is most likely to cause vein irritation and thrombophlebitis when administered via a peripheral IV line?
- Amino acids
- High-concentration dextrose (Correct answer)
- Lipid emulsion
- Multivitamins
Correct answer: High-concentration dextrose
High-concentration dextrose (>10%) is hyperosmolar and causes phlebitis and vein damage, which is why central venous access is required for most TPN formulations.
Question 5: When visually inspecting a lipid-containing TPN (3-in-1) admixture, which finding indicates the emulsion has CRACKED and must be discarded?
- A uniform creamy-white appearance
- A slight yellow tint from multivitamins
- Separation into a visible oil layer on top (Correct answer)
- Small bubbles visible after recent mixing
Correct answer: Separation into a visible oil layer on top
A visible layer of oil separated on top indicates the emulsion has cracked (irreversibly destabilized) and cannot be safely administered.
Question 6: USP <797> requires that high-risk compounded sterile preparations (CSPs) assigned a BUD of more than 12 hours at controlled room temperature must pass which of the following?
- Pyrogen testing only
- Sterility testing only
- Both sterility testing and bacterial endotoxin testing (Correct answer)
- Visual inspection and pH testing only
Correct answer: Both sterility testing and bacterial endotoxin testing
USP <797> requires high-risk CSPs with extended BUDs to undergo both sterility testing and bacterial endotoxin (pyrogen) testing before release.
Question 7: Which amino acid is considered conditionally essential and is commonly added separately to neonatal TPN formulations because it is not stable in standard solutions?
- Glutamine
- Cysteine (Correct answer)
- Tyrosine
- Taurine
Correct answer: Cysteine
Cysteine is conditionally essential in neonates and is unstable in standard amino acid solutions, so it is added separately as cysteine HCl just before administration.
CSPT CSPT - Compounded Sterile Preparation Technician Parenteral Nutrition and IV Admixture Preparation Questions and Answers 4
Which electrolyte is most critical to monitor in patients receiving long-term total parenteral nutrition (TPN) due to the risk of refeeding syndrome?