Sterile Compounding Process and Technique
Process defines the product
Sterile compounding is judged by control of the process, not by the appearance of the final container. The 2023 revision of USP <797> replaced the older low/medium/high-risk framework with Category 1, 2, and 3 CSPs, each with its own maximum beyond-use date (BUD); the category follows from how the CSP is prepared and sterilized, not from the drug or the patient. Immediate-use CSPs (IUSPs) are a separate, narrow pathway: prepared and administered within 1 hour, with contamination risk minimized, and never batch-prepared.
Core technique: work from clean to dirty, keep critical sites (needle hubs, vial septa, syringe tips, ports) in first air, never let a critical site be touched or left uncovered, and stay at least 6 inches inside the ISO 5 PEC with nothing between the HEPA filter and the critical site. Disinfect septa with 70% IPA and allow them to dry.
Traps: assuming a longer BUD because the drug is expensive or the patient needs a supply; confusing 'clean' with 'sterile'; believing a PEC removes the need for technique; and treating an IUSP as a time-saver in the IV room rather than an emergency exception.
Worked example: a nurse requests ten prefilled syringes as IUSPs for a shift. This is not permissible - an IUSP is one patient, one hour. Prepare them as Category CSPs in the PEC with a valid BUD, or abandon the batch.