Effects of intraperitoneal bupivacaine instillation on postoperative pain behavior after laparoscopic ovariohysterectomy in dogs

Abstract

The present study was aimed to investigate the effect of intraperitoneal bupivacaine instillation on postoperative pain after laparoscopic ovariohysterectomy (LOHE) in dogs. Twelve female German shepherd dogs (17-30 kg) were divided into two groups. The treatment group received 4.4 mg/kg of instilled intraperitoneal bupivacaine diluted to 0.25% with an equivalent volume of saline after pneumoperitoneum, but the control group received 1.76 ml/kg of 0.9% saline. Two blind observers measured the extent of dog's pain and sedation by using dynamic interactive visual analogue scale (DIVAS) preoperatively and 0.5, 1, 2, 4, 6, and 12 h postoperatively. At each designated time, blood cortisol, glucose, and creatine kinase (CK) concentrations were also measured. Based on the repeated-measures ANOVA, there were significant differences in time-dependent postoperative changes in patterns of DIVAS-pain score between two groups. In addition, the treatment group had significantly lower DIVAS-pain scores at 1, 2, 4, and 6 h postoperatively compared to the control group. DIVAS-sedation score and biochemical measures including cortisol, glucose, and CK did not show any significant differences between two groups. No complications associated with bupivacaine administration were observed. Thus, instilled bupivacaine intraperitoneally may be an effective method on relieving behavioral expressions associated with postoperative pain after laparoscopic ovariohysterectomy in dogs.