— Drug dispensing robots designed to quickly prepare intravenous medications
in a sterile environment can harbor dangerous bacteria, according to a report
in Infection Control and Hospital Epidemiology, the journal of the Society for
Healthcare Epidemiology of America.
During a routine screening in 2010, personnel at Wake Forest Baptist Medical
Center in North Carolina discovered Bacillus cereus
bacteria in samples dispensed by their machine, the Intellifill IV. “To
our knowledge, this is the first published report of a pharmacy robot being
contaminated with Bacillus with resultant contamination of intravenous drug product,”
the report’s authors write.
Bacillus is a potentially harmful bacterium that is
resistant to many commonly used disinfectants, including alcohol.
Personnel discovered the contamination through quality
assurance measures recommended by the manufacturer before any patients were
harmed by the contaminated drugs. The implications of contaminated intravenous
products can be serious, including potentially life-threatening bloodstream
infections. While any adverse events were avoided, the investigation into how
the machine became contaminated suggests that the current cleaning and
maintenance recommendations may need to be strengthened.
The investigators traced the contamination to the machine’s
washing station and the tubing associated with it. Because this area is not
considered a sterile part of the robot, the manufacturer does not specify a
cleaning procedure for these parts beyond regular “fogging” with
alcohol, using a spray bottle to clean inaccessible parts.
“To prevent other users of Intellifill IV from
experiencing the same problem, the manufacturer should consider establishing a
formal procedure for cleaning and maintaining the washing station, with more
detailed recommendations to change the drain tube, the container, and possibly
the washing station itself,” the authors write. “In addition, it is
reasonable to expand existing quality assurance recommendations to include
surface testing of the washing station and air sampling in the center of the
compartment. Last, using the robot in the pharmacy’s clean room could further
decrease the risk of contamination.”
The findings stress the importance of routine screening of
medication prepared by robotic dispensers, which are increasingly used in
hospitals. “Quality assurance methods are critical to ensure ongoing
patient safety,” the authors write.