Perioperative analgesic effects of the erector spinae plane block with bupivacaine or bupivacaine-dexmedetomidine in dogs undergoing hemilaminectomy: A randomized controlled trial

Objective To compare the perioperative opioid requirements among dogs receiving an erector spinae plane (ESP) block with bupivacaine, with or without dexmedetomidine, and a control group. Animals and procedure Thirty client-owned, healthy adult dogs undergoing hemilaminectomy were included in this randomized, prospective, blinded clinical study. Dogs were randomly assigned to 1 of 3 treatment groups: Group B, ESP block with bupivacaine; Group BD, ESP block with bupivacaine and dexmedetomidine; and Group C, control. Rescue intra- and postoperative analgesia consisted of fentanyl and methadone, respectively. Postoperative pain was evaluated using the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF). Results In Group BD, 0/10 dogs required intraoperative fentanyl, compared to 9/10 in Group C ( P < 0.001), whereas 1/10 required postoperative methadone, compared to 9/10 in Group B ( P = 0.003) and 10/10 in Group C ( P < 0.001). The total amount of intraoperative fentanyl ( mu g/kg) was 0 (0 to 4) in Group B and 0 (0 to 0) in BD, compared to 6 (0 to 8) in C ( P = 0.004 and P < 0.001, respectively). Postoperative methadone (mg/kg) required during the first 12 h was 0.5 (0 to 1.4) in Group B ( P = 0.003) and 0 (0 to 0) in BD ( P < 0.001), compared to C ( P = 0.003 and P < 0.001, respectively). Conclusion An ESP block with bupivacaine, with or without dexmedetomidine, was associated with a reduction in perioperative opioid consumption and provided effective acute pain control.