Clinical evaluation of epidural bupivacaine, butorphanol, and butorphanol -bupivacaine combination in goat

Butorphanol is a synthetic opioid commonly used for epidural anesthesia in human either alone or in combination with bupivacaine but not in goat. The objective of the present study was to evaluate the analgesic effect of epidural butorphanol either alone or in combination with bupivacaine. Fifteen adult apparently healthy goats were randomized into three equal groups to receive a lumbosacral epidural injection of bupivacaine 0.5 % (0.5 mg/kg), butorphanol 1% (0.08 mg/kg) or their combination (bupivacaine 0.25 mg/kg and butorphanol 0.04 mg/kg). Animals were observed for incoordination of hind limbs, perineal pin prick and sedation at 10 minutes interval. Heart rate, respiratory rate and rectal temperature were assessed every 15 minutes. Epidural butorphanol resulted into significantly (P <0.05) rapid analgesia (9.8 ± 1.1 Min) than the butorphanol– bupivacaine combination (12.8 ± 0.84 Min) and bupivacaine (16.6 ± 0.55). Butorphanolbupivacaine combination provoked significant ((P < 0.05) prolonged intense analgesia (208 ± 8.36 Min) compared to either bupivacaine (112 ± 8.37) or butorphanol (166 ± 5.48 Min). Ataxia accompanied administration of bupivacaine either alone or in combination with butorphanol, while sedation was observed in animals received butorphanol alone or combined with bupivacaine. No significant changes were observed in heart rate, respiratory rate or rectal temperature. The epidural administration of butorphanol-bupivacaine combination promoted longer-lasting analgesia in goats without motor disturbances compared to bupivacaine alone. This combination might prove useful clinically to provide analgesia in goats for long-duration perineal obstetrical or surgical procedures.