Comparison of three methods for relief of pain after ear canal ablation in dogs

• Published in: Veterinary surgery Vol. 25; no. 5; p. 380
• Main Authors: Buback, J.L. (Texas AandM Univ., College Station, TX.), Boothe, H.W, Carroll, G.L, Green, R.W
• Format: Journal Article
• Language: English
• Published: United States 01.09.1996
• Subjects: ANAESTHETICS; ANALGESICOS; ANALGESICS; Analgesics, Opioid - therapeutic use; ANALGESIQUE; ANESTESICOS; Anesthesia, Local - methods; Anesthesia, Local - veterinary; ANESTHESIQUE; Animals; Blood Glucose - analysis; Body Temperature - drug effects; Body Temperature - physiology; BUPIVACAINE; Bupivacaine - therapeutic use; CHIEN; DOGS; Dogs - metabolism; Dogs - physiology; Dogs - surgery; DOLOR; DOULEUR; Drug Therapy, Combination; Ear Canal - physiology; Ear Canal - surgery; EARS; Heart Rate - drug effects; Heart Rate - physiology; Hydrocortisone - blood; LATERAL BULLA OSTEOTOMY; MEDICAMENT NEUROTROPE; MEDICAMENTOS NEUROTROPICOS; Nerve Block - methods; Nerve Block - veterinary; NEUROTROPIC DRUGS; OPERACIONES QUIRURGICAS; OPERATION CHIRURGICALE; OPIOIDS; OREILLE; OREJAS; Osteotomy - adverse effects; Osteotomy - veterinary; PAIN; Pain - drug therapy; Pain - etiology; Pain - veterinary; Pain Measurement; PERRO; Preoperative Care - methods; Preoperative Care - veterinary; RESECCION; RESECTION; SURGICAL OPERATIONS; Time Factors
• ISSN: 0161-3499; 1532-950X
• DOI: 10.1111/j.1532-950X.1996.tb01431.x

This study compared three methods of pain relief in dogs that had total ear canal ablation with lateral bulla osteotomy. The hypothesis was that systemic opioids with preoperative local nerve blocks would provide superior pain relief. Thirty-one dogs with chronic otitis externa were included in the study. Dogs were randomly assigned to one of three protocols: systemic opioids alone (10 dogs, group 1), systemic opioids with bupivacaine splash block (11 dogs, group 2), and systemic opioids with preoperative local bupivacaine nerve blocks (10 dogs, group 3). Twenty-one dogs had bilateral ear ablation and 10 had unilateral ablation. Pain was assessed preoperatively, at extubation, 2 hours postextubation, and 1 day postoperatively by a single observer blinded to the analgesic protocol used. Pain scores were not significantly different within or between groups, nor did unilateral versus bilateral ablation have a significant effect on the score. Mean scores were less than 3 (scale 1 to 5) for all groups at all observation times. Rough recoveries were noted in 30% of group 1 dogs, 0% of group 2, and 20% of group 3 dogs. Ninety-four percent of dogs were moderately to heavily sedated at extubation. Sixty percent of group 3 dogs remained moderately to heavily sedated 2 hours postextubation. Rectal temperature, pulse rate, respiratory rate, and postoperative change in serum cortisol levels were not significantly different between groups. Postoperative increase in blood glucose was significantly higher in groups 1 and 3 compared with preoperative levels. Twenty-three percent of the dogs required additional analgesia or tranquilization after surgery, as determined by the anesthetist; 1 dog in group 1, 2 in group 2, and 4 in group 3. Each of the three analgesic protocols provided similar pain relief in dogs undergoing total ear canal ablation.