[S(-) bupivacaine (levobupivacaine) in peripheral blocks: preliminary results]

We have compared the onset time, anesthetic potency and adverse effects of three local anaesthetics (ropivacaine, levobupivacaine and bupivacaine) in two type of peripheral blocks (brachial plexus block for upper limb and femoral nerve block for lower limb) in adult patients in a double blind, randomized, prospective study. A total of 66 patients undergoing orthopaedic surgery were randomly allocated to receive brachial plexus block or femoral nerve blockade with 0,5% ropivacaine (group R, n=22), 0,5% levobupivacaine (group L, n=22) or 0,5% bupivacaine (group B, n=22), each groups has been divided into two subgroups (LBP n=11, RBP n=11, BPB n=11, LBF n=11, RBF n=11, BBF n=11) dipending on the type of block. The onset of sensory nerve block was similar for the three groups; the onset of motor block and onset time ready to surgery were faster in group R (-30%) if compared with group L and B. The duration of motor block and sensory block was respectively longer in group L and in group B. Study results have not been influenced by the blocks, except for plexus nerve block where we observed the same results for group B and group R in relation to onset time ready to surgery. VRS scores were higher in group R as showed by the number of analgesic request in postoperative period. We did not observe any adverse effect. We conclude that ropivacaine acts faster with less interpatient variability, while levobupivacaine and bupivacaine offer a prolonged postoperative analgesia. For this reason, with the exception of bupivacaine due to major cardio and neuro toxicity, we can indifferently use levobupivacaine or ropivacaine depending on the requested characteristics of the anesthetic.