Microbiologic Quality-Control Study for the Purpose of Extending the Use of Transfer Sets on the Automix 3+3 and Micromix Automated Total Nutrient Admixture Compounding Pumps.

BACKGROUND A quality-control study was undertaken by the departments of pharmacy and microbiology at St. Paul's Hospital (Vancouver, British Columbia, Canada) to evaluate the microbiologic safety of total nutrition admixtures (TNA) compounded by automated compounding pumps when the use of disposable transfer sets was extended from 1 day to 2 days. This study also evaluates the potential annual cost savings of this extended use. METHODS Transfer sets and unused part containers of ingredients were left to sit overnight on the automated compounders after daily TNA manufacturing before a TNA sample was compounded for culturing. These TNA samples were cultured using a biphasic system consisting of a tryptic soy broth component and an agar slide component. Positive results were subcultured and isolates were identified by standard methods. Forty samples were collected and evaluated. RESULTS Four bags grew Bacillus species, and 1 bag grew coagulase-negative staphylococci. The potential annual cost savings of this extended use was estimated to be ∼$35,000. CONCLUSIONS The extended use of the disposable transfer sets cannot be instituted at the present time and should be reexamined when the cause(s) of the positive results are identified and corrected.