Monitoring contamination levels of in-use intravenous solutions using “total sample” techniques

Abstract

A monitoring program was developed to compare the bacterial contamination rates of (1) intravenous solutions directly from the manufacturer, (2) i.v. solutions prepared for and infused into patients and (3) i.v. solutions prepared for use but returned to the pharmacy unused. The monitoring system was devised to use an in-line 0.5-μm membrane filter to accomplish “total bottle” sampling. After sampling, the filter unit was inoculated with media and incubated as a sealed unit to test for growth. Of the 155 non control solutions monitored, 4% were found to be contaminated with organisms indicative of a break in aseptic technique. Although solutions with varying numbers of additives were monitored, all contaminated solutions had only one additive. The results suggest that i.v. solutions become contaminated through carelessness in aseptic technique combined with a false sense of security in using a laminar air flow hood.