Evaluation of Topical Epidural Analgesia Delivered in Gelfoam for Postoperative Hemilaminectomy Pain Control

Objective: To evaluate efficacy of a topical epidural analgesia used alone, or in combination with hydromorphone, against a standard pain protocol for the 48 hours immediately after hemilaminectomy. Study Design: Randomized, blinded, controlled, clinical trial. Animals: Dogs (n = 30) with thoracolumbar intervertebral disc disease treated with hemilaminectomy. Methods: Dogs were randomly divided into 3 groups: group 1 received intermittent hydromorphone postoperatively, group 2 received a topical epidural of preservative-free morphine and dexmedetomidine administered via gel foam, group 3 received both forms of analgesia. All dogs were monitored and assessed for pain for 48 hours immediately postoperatively. Data were analyzed using MANOVA and Wilcoxon Rank Sum Tests. Results: There was a significant temporal difference in treatment groups 1 and 3 when using a 0-10 pain scale (MANOVA, P = .02). There was also a significant difference at the 48th hour postoperatively between groups 1 and 3 (Wilcoxon Rank Sum Test). Conclusion: Topical epidural of preservative-free morphine and dexmedetomidine administered via gelfoam is not sufficient analgesia alone post hemilaminectomy but in conjunction with other opioid administration may lead to superior pain relief.