A COMPARISON BETWEEN INTRAVENOUS OXYMORPHONE AND EPIDURAL BUPIVACAINEALONE AND IN COMBINATION WITH OXYMORPHONE

The purpose of this study was to compare the effects of epidural bupiv acaine (BUP) and oxymorphone/bupivacaine (O/B) and intravenous (IV) ox ymorphone (IVO) on halothane requirements during hind end surgery;Ind postoperative analgesia in 24 dogs. Dogs were randomly assigned to tre atment groups: O/B - oxymorphone (0.1 mg/kg) in 0.75% bupivacaine (1 m g/kg for a total volume of 0.2 ml/kg); BUP -0.5% bupivacaine (1 mg/kg for a total volume of 0.2 ml/kg) with IV oxymorphone (0.05 mg/kg) post operatively; and IVO - oxymorphone (0.05 mg/kg) pre- and postoperative ly. Heart rate (HR), respiratory rate, arterial blood pressure, end-ti dal carbon dioxide and halothane, and arterial blood gases were record ed prior to treatment and every 15 minutes thereafter. Once surgery ha d begun, end-tidal halothane concentrations were decreased as low as p ossible while still maintaining a stable anesthetic plane. Data were a nalyzed using ANOVA with P < 0.05 considered significant. End-tidal ha lothane requirements did not differ significantly among treatments. Re spiratory depression was increased and HR was decreased in the O/B and IVO groups. Postoperative analgesic requirements were significantly l ess in dogs receiving O/B.