Sterility of anesthetic multiple-dose vials after opening

Area of Science:

• Anesthesiology
• Microbiology
• Healthcare Infection Control

Background:

• Multiple dose vials (MDV) are frequently used for anesthetic medications.
• Limited data exists on the sterility of in-use MDVs in clinical practice.

Purpose of the Study:

• To investigate the frequency of bacterial contamination in in-use MDVs during anesthesia procedures.
• To assess the impact of duration of use and surgical setting on vial sterility.

Main Methods:

• Weekly sampling of 351 in-use MDVs containing various anesthetic drugs over seven weeks.
• Culturing of samples using appropriate bacterial growth media.
• Analysis of contamination rates based on vial usage duration (6-48 days) and surgical location (elective vs. emergency).

Main Results:

• No bacterial contamination was detected in any of the cultured MDVs.
• Vials remained in use for up to 48 days, with half used beyond 4-9 days.
• Contamination rates were low regardless of extended use or emergency surgery settings.

Conclusions:

• The incidence of bacterial contamination in in-use MDVs for studied anesthetic medications is low.
• Current practices appear to maintain vial sterility, even with prolonged use and in high-risk surgical environments.