Review of studies examining microbial contamination of vials used for preparations done with closed-system drug transfer devices.

OBJECTIVES: The main objective was to identify all studies that present data regarding microbial contamination of vials used for preparation with closed-system drug transfer devices (CSTDs). Our secondary objective was to compare the reported contamination of vials punctured with a CSTD versus no CSTD and to evaluate the quality of data reporting as defined by the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria.

METHODS: A literature review was conducted on 31 December 2018 on PubMed, EMBASE and Cumulative Index to Nursing and Allied Health Literature. A manual search of the archives of relevant pharmaceutical conferences was made. All studies that presented data about microbial contamination of vials punctured with a CSTD or about beyond-use date extension were included. Two researchers independently graded the articles according to the STROBE criteria.

RESULTS: Of the 280 articles identified initially, 12 were retained for analysis. Studies evaluated microbial contamination according to different incubation times and different culture media. Nine studies did not use any comparator group. Five studies found no contamination of vials punctured with CSTDs. For the others, the contamination was between 0.3% and 27%. Three studies compared the contamination of vials punctured with a CSTD and with a conventional system and did not show a significant difference between the groups. Seven studies declared a conflict of interest. The mean number of STROBE criteria fulfilled was 12.2±4.1 out of 34 (7 not applicable) for studies, and the mean number was 5±0 out of 12 for abstracts.

CONCLUSIONS: Vials punctured in ISO5 conditions with a CSTD presented a low frequency of microbial contamination. No study showed a significant difference between vials punctured with a CSTD and with a conventional method. Centre-specific sterility testing is needed to reflect the variability of handling procedures and equipment.