Comparison of continuous brachial plexus infusion of butorphanol, mepivacaine and mepivacaine-butorphanol mixtures for postoperative analgesia.

Abstract

We have reported recently that continuous administration of butorphanol into the brachial plexus sheath provided analgesia of a quality superior to that of continuous i.v. administration. In the present study, we have compared postoperative pain relief produced by continuous infusion of one of three types of solution into the axillary sheath: opioid alone, local anaesthetic alone or a mixture of local anaesthetic and opioid. In patients undergoing upper extremity surgery with continuous axillary brachial plexus block, we injected one of the three solutions into the axillary neurovascular sheath: butorphanol 2 mg (group B), 0.5% mepivacaine alone (group M) and 0.5% mepivacaine-butorphanol (group MB); the volume of each solution was 50 ml, administered at a rate of 50 ml per 24 h. At 3 h after operation, visual analogue scale (VAS) scores were significantly higher in group M than in group MB (P < 0.01), and higher in group B than in group MB (P < 0.05).