A comparison of epidural levobupivacaine 0.75% with racemic bupivacaine for lower abdominal surgery

Levobupivacaine, the S(-) isomer of bupivacaine, is less cardiotoxic than r acemic bupivacaine. In this prospective, randomized, double-blinded study o f epidural anesthesia, the onset, extent, and duration of sensory and motor block produced by 0.75% levobupivacaine (20 mL, 150 mg) was compared with that of 0.75% racemic bupivacaine in 56 patients undergoing elective lower abdominal surgery. The time to onset of adequate sensory block(T10 dermatom e) was similar in both treatment groups (13.6 +/- 5.6 min for levobupivacai ne and 14.0 +/- 9.9 min for bupivacaine), with an average peak block height of T5 reached at 24.3 +/- 9.4 and 26.5 +/- 13.2 min, respectively. Time to complete regression of sensory block was significantly longer with levobup ivacaine (550.6 +/- 87.6 min) than bupivacaine (505.9 +/- 71.1 min) (P = 0. 016). Abdominal muscle relaxation was adequate for the scheduled procedure in patients, and there were no significant differences between the groups i n rectus abdominis muscle scores (P = 0.386) and quality of muscle relaxati on as determined by the surgeon and anesthesiologist (P = 0.505 and 0.074, respectively). In conclusion, both 0.75% levobupivacaine and 0.75% bupivaca ine produced effective epidural anesthesia and their effects were clinicall y indistinguishable. Implications: The results of this study indicate that the sensory and motor block produced by 0.75% levobupivacaine is equivalent to that of 0.75% racemic bupivacaine. Both local anesthetics are well tole rated and effective in producing epidural anesthesia for patients undergoin g lower abdominal surgery.