Regional anesthesia techniques are becoming increasingly popular in veterinary medicine. This is because they offer localized pain relief while potentially reducing the need for systemic opioid analgesics during the perioperative period. One such technique is the GIN-TONIC block, a combination of the greater ischiatic notch plane block and the caudal lateral quadratus lumborum block, which was recently investigated for its analgesic and motor effects in dogs undergoing pelvic limb surgery.
Two Dozen Dogs in Study
This pilot study, conducted by a team of veterinary researchers, involved 24 dogs scheduled for pelvic limb orthopedic procedures. The dogs were randomly divided into two equal groups: Group GA (acepromazine premedication) and Group GD (dexmedetomidine premedication). Both groups received a GIN-TONIC block using 2% lidocaine during the surgical procedure, and general anesthesia was maintained with isoflurane.
Assessing Nociception and Postoperative Pain
The researchers closely monitored the dogs for signs of nociception (pain) during the surgical procedure. If nociception was observed, the dogs received a rescue dose of fentanyl (2 ?g kg–1 IV). Postoperative pain was assessed using the Glasgow Composite Measure Pain Score (GCMPS-SF), and any dogs exceeding the predefined pain threshold were administered morphine (0.5 mg kg?1 IV) during the recovery period.
Evaluating Motor Function
In addition to assessing pain, the researchers also evaluated the dogs’ motor function during the recovery period. They used descriptors previously reported in the literature to assess the dogs’ ambulation and ability to stand without assistance.
Key Findings
The results of the study were promising. Postoperative pain scores remained low (?4/20) for all but one dog, indicating effective pain management with the GIN-TONIC block. Only three dogs in Group GD and two in Group GA required a single dose of fentanyl during the surgical procedure. Additionally, the dogs in both groups achieved non-ataxic ambulation within 35-39 minutes after extubation, demonstrating well-preserved motor function.
GIN-TONIC Block Shows Promise
This pilot study highlighted the potential of the GIN-TONIC block as a feasible regional anesthesia method for delivering perioperative analgesia in dogs undergoing pelvic limb orthopedic surgery. The findings suggest this technique may provide effective pain relief while preserving motor function, which could be particularly beneficial for patients undergoing complex orthopedic procedures.
While the results of this study are promising, the authors acknowledge that further clinical exploration, including prospective randomized controlled trials, is necessary to solidify the efficacy of the GIN-TONIC plane block in this context. As regional anesthesia techniques continue to evolve in veterinary medicine, studies like this contribute to our understanding of the potential benefits and limitations of these innovative approaches to pain management in canine patients.
