Modulatory Effect Of Dezocine On Remifentanil-induced Hyperalgesia For Patients Undergoing Major Abdominal Surgery: A Prospective Study

Objective Remifentanil–induced hyperalgesia (RIH),documented both experimentally and clinically, has become aclinical challenge. Dezocine, an opioid μ partialagonist/antagonist, is an alternative medication forperioperative pain mangement, which has also a modulatory effectfor thermal hyperalgesia. The goal of our study is to show whethersingle doses of dezocine is effective for RIH.Methods Fifty patients undergoing open gastrectomy were randomlyassigned to (1) dezocine group,0.15mg/kg dezocine at the end ofsurgery and (2) control group, the same volume of normal salin atthe end of the surgery. Cumulative PCA consumption was recordedat6and24postoperative hours. Pain scores were noted for48hoursafter surgery. Sedation scores and rescue analgesics use wererecorded every30min during PACU stay. Pain thresholds to Von Freyfilaments were tested preoperatively and at6hours,24hours and 48hours postoperatively. Anesthesia associated complicationssuch as nausea, vomiting and prurits were also recorded.Results The hyperalgesia to Von Frey filament stimulation on theforearm and the extent of hyperalgesia proximal to the surgicalwound were larger (p <0.05) in the control group. Thepostoperative analgesic demand was less in dezocine group (p <0.05). Patient characteristics data, intraoperative status,adverse effects and periincisional hyperalgesia were comparablebetween two groups.Conclusion Dezocine is a potential adjunctive drug to modulatepostoperative RIH without any adverse effects with a dose of0.15mg/kg at the end of surgery. But further investigations arewarranted to illustrate the precise mechanisms.