[Levobupivacaine for parturients undergoing elective caesarean delivery. A dose-finding investigation]

The optimum intrathecal dose of hyperbaric levobupivacaine for spinal anaesthesia during elective caesarean section has not yet been investigated.

A total of 30 parturients undergoing elective caesarean section were included in this prospective, randomised, double-blind study. Parturients received either 7.5, 10 or 12.5 mg hyperbaric 0.5% levobupivacaine intrathecally. Analgesic, sensory and motor block characteristics as well as maternal and fetal levobupivacaine plasma concentrations were determined.

Of the parturients receiving 7.5 mg levobupivacaine 40% required supplementary intravenous opioid analgesics intraoperatively and none achieved complete motor block. Compared to 7.5 mg levobupivacaine, 10 and 12.5 mg significantly prolonged duration of effective analgesia postoperatively (median: 45 vs. 81 and 96 min, respectively). Both maternal and fetal levobupivacaine plasma concentrations were low, with dose-dependent, statistically significant differences in maternal plasma concentrations.

Levobupivacaine 7.5 mg did not provide satisfactory intraoperative analgesia in all parturients. There were no statistically significant differences between 10 and 12.5 mg levobupivacaine with respect to analgesic, sensory and motor block characteristics. Therefore, based on these data, 10 mg levobupivacaine is recommended for parturients undergoing elective caesarean section with spinal anaesthesia.