The effect of lidocaine on bacterial growth in propofol

dExtrinsically contaminated propofol has been associated with multiple infe ctious complications. Injection of propofol is associated with pain that is diminished by the addition of lidocaine. Lidocaine has antibacterial prope rties at high concentrations, but low concentrations of lidocaine (0.1%) ha ve not been studied. We examined the growth rates of Staphylococcus aureus, Serratia marcescens, Pseudomonas aeruginosa, and Candida albicans in propo fol containing disodium edeteate with and without added lidocaine 0.1% 2, 5 , and 24 h after inoculation. There was no significant difference in the nu mber of colony-forming units between propofol with and without added lidoca ine at any time after inoculation. Implications: The addition of Lidocaine to propofol in concentrations clinically effective in reducing pain on inje ction had no effect on microbial growth. Adherence to strict aseptic techni que is further emphasized.