In vitro investigation of the antibacterial activity of levobupivacaine on pseudomonas aeruginosa

The antibacterial activity of local anesthetics is one of the major barriers to prevent occurrence of epidural catheter-related infections.In this study, it was aimed to investigate the antibacterial activity of levobupivacaine on Pseudomonas Aeruginosa experimentally through the Patient Controlled Epidural Analgesia Model, at two concentrations chosen for postoperative pain treatment (0.125%) and painless childbirth procedures (0.0625%) in our hospital.Working solutions were prepared as 100 ml. Contents of the solutions were as follows: Group 1 (n = 10): 0.125% levobupivacaine + 4 ml of fentanyl (200 ?g), Group 2 (n = 10): 0.0625% levobupivacaine + 4 ml of fentanyl (200 ?g), Group 3 (n = 10): 4 ml of fentanyl (200 ?g), Group 4 (n = 10): 99 ml of normal saline. 1 ml of Pseudomonas Aeruginosa 0.5 McF (3x106 cfu/ml) was added to all groups.Samples of the groups (n = 40) were filtered through EGEMEN brand bacteria filter, infused with the Patient Controlled Analgesia device at a rate of 5 ml / h, and collected at sterile bottles. Samples taken from the bottles (n = 40), filter inputs (n = 40) and filter outlets (n = 40) were cultured on Blood Agar, and bacterial colony count were determined for each sample. Results were analysed with the SPSS 15.0 program. In statistical analysis, Kruskal-Wallis test was used to determine differences between the goups, and Mann- Whitney-U test was used to compare two groups. p <0.05 was considered statistically significant.Our findings showed that all of the solutions significantly decreased the number of colonies of Pseudomonas Aeruginosa (p <0.05). The number of colonies decreased as the concentration of levobupivacaine increased, but this correlation was not found statistically significant (p> 0.05). Our data revealed that holding capacity of the bacteria filter wass? 100% for Pseudomonas Aeruginosa.Based on these results, we concluded that levobupivacaine, which is widely used in patient controlled epidural analgesia, showed antibacterial activity against Pseudomonas aeruginosa, fentanyl was also effective against Pseudomonas aeruginosa, and when used concomitantly with levobupivacaine, it increased overall antibacterial activity, and could be considered as an additional barrier reducing the risk of infection.Key words: Levobupivacaine, antibacterial activity, Patient Controlled Analgesia Device, Pseudomonas Aeruginosa, epidural