Propofol contamination in an emulsion formulation, has been associated with infective complications. It becomes contaminated once the ampoules have been opened. Propofol contamination supports the growth of all microorganisms.
Diphtheroid bacilli and coagulase-negative staphylococci were the most frequent microorganisms. Others are E. coli, S. aureus, and P. aeruginosa.
Adding lidocaine, or storing opened ampoules at 12-14 degrees C, does not affect the contamination rate, except during the first few hours.
It is advisable to draw propofol aseptically as recommended by manufacturers of propofol, into a syringe in an amount that can be used during one procedure. EDTA added to propofol retards microbial growth.