CSPT - Compounded Sterile Preparation Technician Parenteral Nutrition and IV Admixture Preparation Questions and Answers Flashcards

Which electrolyte is most critical to monitor in patients receiving long-term total parenteral nutrition (TPN) due to the risk of refeeding syndrome?

Answer: Phosphate

Phosphate drops precipitously during refeeding syndrome as cells take up phosphate rapidly during anabolism, making it the most critical electrolyte to monitor.

When preparing a TPN admixture, dextrose is added before lipid emulsion in a 3-in-1 (total nutrient admixture) primarily to:

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.

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?

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.

Which component of a TPN formulation is most likely to cause vein irritation and thrombophlebitis when administered via a peripheral IV line?

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.

When visually inspecting a lipid-containing TPN (3-in-1) admixture, which finding indicates the emulsion has CRACKED and must be discarded?

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.

USP 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?

Answer: Both sterility testing and bacterial endotoxin testing

USP requires high-risk CSPs with extended BUDs to undergo both sterility testing and bacterial endotoxin (pyrogen) testing before release.

Which amino acid is considered conditionally essential and is commonly added separately to neonatal TPN formulations because it is not stable in standard solutions?

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.