ExCPT · Dispensing Process · 6 min read
Sterile Compounding: USP 797, Aseptic Technique and PPE
- Differentiate the professional duties of the pharmacy technician from the legal responsibilities of the licensed pharmacist during sterile compounding.
- Describe the garbing sequence, hand hygiene procedures, and engineering controls required by USP Chapter 797.
- Apply aseptic manipulation principles, critical site management, and vial-entry techniques to prevent contamination of compounded sterile preparations.
Technician Scope of Practice and Pharmacy Regulations
Pharmacy technicians prepare compounded sterile preparations under pharmacist supervision in accordance with applicable law and facility policy; whether supervision must be direct depends on the jurisdiction. Technicians play a vital hands-on role in maintaining cleanroom conditions, gathering supplies, and performing manipulations inside the primary engineering control. Once compounding is complete, the pharmacy technician carefully inspects the preparation for container leaks, precipitation, particulate matter, and signs of coring.
While technicians perform the preparation, the licensed pharmacist holds the legal responsibility for the final verification of every compounded sterile preparation. Furthermore, responsibilities requiring clinical judgment, such as drug regimen reviews and patient counseling, belong strictly to the pharmacist and cannot be delegated to technicians.
To ensure patient safety, USP Chapter 797 establishes rigorous standards for compounding sterile preparations to prevent contamination and patient harm. Technician competency is assessed through formal testing, which includes gloved fingertip and thumb sampling, media-fill testing, and additional assessments required by USP <797>.
Common mistakes
- Using sterile water alone to clean laminar airflow workbenches, forgetting that sterile water lacks disinfecting properties and that sterile 70% isopropyl alcohol must be used.
- Injecting fluid back into a final preparation using the same filter needle that was used to withdraw medication from an ampul, which re-injects trapped glass shards.
- Touching the plunger shaft of a syringe during manipulation, which contaminates a critical site that slides directly into the sterile syringe barrel.
- Recapping needles with both hands instead of using a one-handed technique or an appropriate mechanical device when recapping cannot be avoided.
Key points
- Pharmacy technicians prepare sterile compounds under a licensed pharmacist's supervision, but final verification, drug regimen review, and patient counseling remain the exclusive legal responsibility of the pharmacist.
- USP Chapter 797 establishes environmental standards, including ISO Class 5 for primary engineering controls, ISO Class 7 for buffer areas, and ISO Class 8 for positive-pressure ante-areas.
- Garbing must proceed in order from less-clean to cleaner areas, ending with hand drying using low-lint towels, gowning, alcohol-based hand rub, and donning sterile powder-free gloves.
- First air exiting the HEPA filter must reach all critical sites unobstructed; critical sites like syringe tips, plunger shafts, needle hubs, and bevels must never be touched.
- To reduce vial-stopper coring, puncture the rubber stopper with the needle bevel facing up at a 45-degree angle before straightening it into the vial.
- Liquids drawn from snapped glass ampuls must be filtered using a filter needle or filter straw to capture glass shards, and the filter needle must be replaced before injection.
- Single-dose vials generally lack preservatives and must be used or discarded within applicable USP <797> and manufacturer limits; multiple-dose vials usually contain antimicrobial preservatives and generally must be discarded within 28 days after initial puncture unless the manufacturer specifies otherwise.
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