Propofol emulsion and bacterial contamination

Package insert information provided with propofol advises prompt administration following its drawing-up. This study has examined the delays which occur between drawing-up and administration of propofol in clinical practice and the incidence of bacterial contamination occurring under such conditions. Two hundred and fifty-four clinical uses of propofol were examined. Mean elapsed times (range) from drawing-up to induction were 28.8 min (1-172), and 11.6 min (1-65) from induction to culture inoculation. The delay to induction exceeded ten minutes in 68.5% of propofol uses. Sixteen cultures (6.3%) grew bacteria. Delay to induction was not associated with increased chances of bacterial growth in any of the samples. Increasing delay between induction and culture inoculation was associated with greater odds of bacterial growth, which is consistent with contamination occurring at or after induction. Whilst the manufacturers advise prompt administration, our findings show that when inadvertent delays occur, propofol remains bacteriologically safe to use under standard clinical conditions. Microbial contamination can occur at any stage, thus attention to asepsis remains important throughout the administration period.