ABSTRACT
Levobupivacaine is the isolated Senantiomer of bupivacaine and may be a favorable alternative to spinal bupivacaine. However, its clinical efficacy relative to bupivacaine and its dose-response characteristics, in spinal anesthesia, must first be known. This, double-blinded randomized, study was designed to compare the clinical efficacy of hyperbaric levobupivacaine and bupivacaine for spinal anesthesia. Forty patients undergoing elective lower limb orthopaedic surgeries received either 3.5 mL levobupivacaine 0.5% hyerbaric or 3.5 mL bupivacaine 0.5% hyerbaric. Sensory blockade was assessed with the pinprick test; motor blockade was documented by using a modified Bromage score. Haemodynamic variables [e.g., blood pressure, heart rate, pulse oximetry] were also recorded as well as time for discharge criteria. In both groups sensory and motor block were similar between the same doses of levobupivacaine and bupivacaine [P > 0.06]. The duration of motor block at the quadriceps was 281 +/- 48 versus 284 +/- 4.2 min levobupivacaine and racemic bupivacaine respectively. Intergroup differences between levobupivacaine and bupivacaine were insignificant both in respect to the onset time and the duration of sensory and motor blockade [11.8 +/- 1.4 versus 12 .4 +/- 1.1 min; 10 +/- 3 versus 9 +/- 3 min; 225 +/- 50 versus 235 +/- 47min; 281 +/- 48 versus 284 +/- 42 min]. There were no statistically significant differences between the two groups except for the fact that the transition from Bromage scale 0 to 2 was significantly faster in the Levobupivacaine [4 +/- 1 min] than in the Bupivacaine group [7 +/- 2 min]. By comparison, there was no significant difference in first VAS scores at the PACU [3.1 +/- 0.5] in the Levobupivacaine versus [3.4 +/- 0.8] in the bupivacaine group. In both groups slight reductions in heart rate and mean arterial pressure were recorded, but there was no intergroup statistical difference haemodynamic parameters. There was no significant difference with regards time until achievement of discharge criteria. We conclude that intrathecal levobupivacaine is equal in efficacy to racemic bupivacaine