Brachial plexus block with opioids for postoperative pain relief: comparison between buprenorphine and morphine

The effectiveness of buprenorphine and morphine, administered into the brachial plexus sheath, was evaluated in 40 patients, aged 18-90 years. All patients received 40 ml of 0.5% bupivacaine, injected into the brachial plexus sheath using the supraclavicular technique. In addition, the 20 patients in Group I received morphine hydrochloride (50 micrograms/kg), while the 20 patients in Group II received buprenorphine hydrochloride (3 micrograms/kg). Using a three-point pain scale, the quality of analgesia was evaluated every hour for six hours, every two hours for the next six hours, and then at 12, 24, 36 and 48 hours. A significant difference in the quality of analgesia was found; and was consistently superior with buprenorphine as compared with morphine. The duration of analgesia was nearly twice as long in the buprenorphine group as in the morphine group (35.05 +/- 1.95 hour versus 18.25 +/- 1.15 hour). We conclude that buprenorphine injection into the brachial plexus sheath is an efficient way to assure control of postoperative pain after upper limb surgery.