BACKGROUND: Local anesthetic infiltration along the incision may be used to provide surgical anesthesia or postoperative analgesia. However, the effect of local anesthetics on wound healing remains controversial. In this investigation, we evaluated the effects of levobupivacaine on wound healing.
METHODS: Sixty Wistar albino female rats weighing 230 +/- 20 g were included, with 10 rats in each group: group early c (early control): 3 mL isotonic saline; group early I-1.25 (early levobupivacaine 1.25): 1.25 mg/kg per 3 mL levobupivacaine; group early I-2.5 (early levobupivacaine 2.5): 2.5 mg/kg per 3 mL levobupivacaine; group late c (late control): 3 mL isotonic saline; group late I-1.25 (late levobupivacaine 1.25): 1.25 mg/kg per 3 mL levobupivacaine; and group late I-2.5 (late levobupivacaine 2.5): 2.5 mg/kg per 3 mL levobupivacaine. Rats in groups early c to early I-2.5 were euthanized on the 8th day. Rats in groups late c to late I-2.5 were euthanized on the 21st day. Wound tension strength, tissue hydroxyproline, and fibrotic index levels of the tissue samples from the early c and early I-2.5 and late c and late I-2.5 groups, respectively, on the 8th and 21st days were examined.
RESULTS: Levobupivacaine decreased wound tension strength on the 8th day, especially a 2.5 mg/kg dose (P < 0.001), and increased it on the 21st day (P < 0.001). It also increased the inflammatory response (P < 0.001) and collagen synthesis (8th day, P = 0.109; 21st day, P = 0.103) on both the 8th and 21st days.
CONCLUSIONS: While levobupivacaine had a positive effect on wound healing during the early period, negative effects were observed thereafter. Additional studies at the molecular level are necessary to determine the cause of these apparently opposite effects. (Anesth Analg 2013;116:495-9)