Joseph A Gentempo | Search PubMed

PubMed2005

Using a medium-fill simulation to evaluate the microbial contamination rate for USP medium-risk-level compounding.

PURPOSE: The estimated microbial contamination rate for complex, multiple-step, medium-risk-level compounding was studied. METHODS: The results of evaluations of the aseptic technique of pharmacists and technicians in compounding complex USP medium-risk-level sterile preparations were compiled to estimate the microbial contamination rate. The testing took place in 2002 and 2003 at a single institution and involved reconstitution of sterile dry growth medium and a series of complicated transfers of the medium from vials and ampuls to intravenous bags. The bags were incubated at 25-35 degrees C for 14 days and observed for microbial growth. RESULTS: Of 539 evaluations, 28 (5.2%) resulted in preparations that yielded microbial growth. Pharmacists' compounding resulted in a slightly lower contamination rate (4.4%) than that of technicians (6.2%). Inadvertent touch contamination may have been the principal source of the contamination. CONCLUSION: . A two-year series of 539 evaluations of the aseptic technique of pharmacists and technicians conducted with sterile growth medium and designed to simulate the compounding of USP medium-risk-level sterile preparations yielded an overall contamination rate of 5.2%.

Drug Compounding↗

PubMed2003

Using medium-fill simulation to establish a benchmark microbiological contamination rate for low-risk-level compounding.

A benchmark contamination rate for prefilled syringe compounding was determined by using a medium-fill-simulation method. One thousand thirty-five 1-mL tuberculin syringes were aseptically filled with 0.9 mL of sterile soybean-casein digest medium and capped. These syringes were placed into clear nonsterile plastic bags and incubated at 35 degrees C for seven days, then inspected for cloudiness or colony formation indicative of bacterial growth. The operation was performed by two certified pharmacy technicians in an ISO Class 5 vertical-airflow biological safety cabinet in a typical inpatient pharmacy compounding area over two days. The technicians wore protective garments and gloves and followed standard procedures of preparing sterile injections. The adequacy of the methodology was verified by using four syringes that contained deliberately contaminated medium and incubating them along with 15 aseptically prepared syringes at 35 degrees C for seven days. Colony formation in the four syringes containing contaminated medium was directly observed and differentiated from the control syringes, which confirms the validity of the method. No bacterial growth was detected in any of the 1035 medium-filled syringes studied. Therefore, the contamination rate for aseptic compounding operation was less than 0.1%. Medium-fill-simulation testing of 1035 prefilled tuberculin syringes yielded no contamination. A contamination rate of less than 0.1% should be achievable and expected for this type of low-risk pharmacy preparation after pharmacies validate their own compounding operation.

Bacteria↗