Background and objectives: Over two decades, results of studies evaluating the analgesic effect of opioid and local anesthetic combination in the brachial plexus block were inconclusive. The aim of this study was to compare the duration of analgesia produced by lidocaine alone or the combination of lidocaine and 0.1 mg.kg -1 morphine. Methods: In a randomized, prospective, double-blinded trial, 60 patients (ASAI-II), aged 16-70 years undergoing brachial plexus block (supraclavicular approach) for upper limb surgery were randomly allocated to 2 groups. Group C (n=30) were received 25 ml. Of 1.5% lidocaine with epinephrine 1 : 200,000 solution. Group M (n=30) were received the same solution as group C plus morphine 0.1 mg.kg.-1 The onset time, duration of sensory / motor block and duration of postoperative analgesia were noted. Results: There was no significant difference between groups in onset time of sensory and motor block. Duration of motor block in group M was significantly longer than group C (p<0.05) whereas the duration of sensory block was not. The median duration of postoperative analgesia was 3.67 hours (25 th – 75 th ) percentiles : 2.93 – 4.5 hours) in group M and 3.1 hours (25 th – 75 th percentiles : 2.18-4.5 hours) in group C which was not significantly different (P=0.84). Conclusion: The addition of morphine 0.1 mg.kg-1 to 25 ml. Of 1.5% lidocaine with epinephrine solution for the supraclavicular brachial plexus block does not improve the duration of postoperative analgesia but prolongs the duration of motor blockade.

วิสัญญีสาร ปี 2548, April-June ปีที่: 31 ฉบับที่ 2 หน้า

postoperative analgesia, Brachial plexus block, morphine, opioids