Analgesic Effect of Local Infiltration of the Surgical Wound Containing Levobupivacaine, Ibuprofen, and Epinephrine in Rats Undergoing Laparotomy.

Abstract

Inappropriate use of drugs and their combinations for analgesics has made it difficult to determine the optimal drug combinations for pain mangement. To reduce postoperative pain effectively and safely. Laparotomy was performed in an adult rat under isoflurane anesthesia. During surgery, the surgical wounds were infiltrated with 50 μL solution containing 0.3% w/v levobupivacaine, 2 mg/mL ibuprofen, and 8 mg/mL epinephrine (treatment group) over the sutured muscle wound before skin closing, and compared to infiltration of that of the normal saline (vehicle group). The 10-fold higher dose of the same combination of medications was injected systemically as a control. Postoperative pain assessed by rodent grimace scales scoring. One-way ANOVA following Dunnett multiple comparisons test was used at 95% of confidence level. There was decreased pain for the treatment group (p = 0.025, q = 4.527) and the control group (p = 0.031, q = 4.178) only 24 h after the end of the successful infiltration. The rodent GS scale scoring showed the fall in pain was started within three hours post-surgery in the treatment group. There was decreased pain in the treatment group (p = 0.048, q = 3.527) and the control group (p = 0.043, q = 3.891) only as compared to vehicle group 24 h after the end of the successful infiltration. The infiltration of the surgical wound with levobupivacaine, ibuprofen, and epinephrine combination was effective in the healing of wounds after laparotomy.