Effects of epidural anaesthesia–analgesia on intravenous anaesthesia with propofol

The main purpose of this study was to demonstrate that the use of epidural anaesthesia–analgesia reduces the amount of propofol necessary to maintain surgical anaesthesia in dogs during ovariohysterectomy. The study was carried out on 28 bitches undergoing ovariohysterectomy with general anaesthesia using an intravenous infusion of propofol. Dogs were allocated to one of two groups. Group 1 received systemic buprenorphine together with epidural analgesia using lidocaine and buprenophine, and in Group 2 systemic buprenorphine only was given. The mean propofol infusion rate was significantly lower in dogs with epidural analgesia (P<0.0001). In addition, the mean endotracheal extubation time was significantly longer in dogs with epidural analgesia (P<0.0001). No significant differences were detected in any of the physiological parameters measured.