RESUMEN
OBJECTIVE: To determine the growth of microorganisms in propofol when combined with fentanyl and lidocaine in different temperatures and times in order to find out whether there is any improvement in antimicrobial effect to lengthen the safe duration of time for application of propofol. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Istanbul Aydin University Laboratory, Istanbul, Turkey, from June to September 2018. METHODOLOGY: The studied drugs and thier combination was used to determine their effect on bacterial growth of Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Acinetobacter baumanni. Bacterial solutions were prepared at 0.5 MacFarland in sterile 0.9% physiological saline and diluted at 1:100 concentration. Colony numbers were measured as colony forming units mL-1 at 0, 8, and 24 hours and at 4oC, 22oC and 37oC. RESULTS: In general, propofol supported the growth of microorganisms. Fentanyl with propofol also promoted the growth, especially in room and body temperature at 8th and 24th hours but when combined with lidocaine, the number of CFUs was reduced significantly compared with propofol + fentanyl group. Lidocaine inhibited the growth of microorganisms in all the solutions except for candida albicans. CONCLUSION: Lidocaine was shown to have antibacterial effect which carries advantage for inhibiting infections due to propofol; but aseptic technique is essential during preparation of propofol infusions. Fentanyl like propofol also promoted the growth at room and body temperatures.