BRACHIAL-PLEXUS BLOCK - EFFECT OF THE ADD ITION OF SUFENTANIL TO THE MIXTURE OF LOCAL-ANESTHETICS ON DURATION OF POSTOPERATIVE ANALGESIA

Objectives: To compare the quality and the duration of analgesia produ ced by a supraclavicular brachial plexus blockade obtained with a mixt ure of lidocaine and bupivacaine when supplemented or not with sufenta nil. Study design: Prospective, randomized, double-blind study. Patien ts: The study included 40 patients undergoing osteosynthesis of the up per limb under brachial plexus block, randomly assigned to two groups. Methods: The patients of the control group were given 0.5% bupivacain e 1 mg . kg(-1) and 1% lidocaine 2 mg . kg(-1). Those of the sufentani l group, received the same mixture supplemented with sufentanil 0,2 mg . kg(-1). During the postoperative period, the characteristics of ana lgesia were blindly evaluated every hour for 48 h with a visual analog ic scale graduated from 0 to 100. Analgesia was considered satisfactor y when the score was below 30. Adverse effects of opiates (drowsiness, pruritus, nausea and vomiting) were also assessed. Oxygen saturation was continuously monitored. Blood pressure, heart and respiratory rate s were measured at the same intervals than analgesia. Duration of anal gesia are expressed as medians (range) and compared using a Mann and W hitney's U test. Results: The respective durations of satisfactory ana lgesia were significantly different. 12.5 h (8-17) in the control grou p versus 24 h (8-48) for the sufentanil group. The adverse effects in the sufentanil group were nausea (2), vomiting (1) and pruritus (1). N o respiratory depression was noted. Conclusion: Sufentanil added to a mixture of lidocaine and bupivacaine increases twofold the duration of postoperative analgesia following brachial plexus blockade.