Background and objectives: Local anesthetic bupivacaine is found in two different enantiomers: levobupivacaine - S (-) and dextrobupivacaine - R (+). Based on studies showing that S(-) enantiomers are less cardiotoxic, their use has been increasing in clinical practice. This study aimed at comparing racemic bupivacaine and levobupivacaine in epidural anesthesia for elective cesarean section.
Methods: Randomized, double blind clinical trial enrolling physical status ASA I and II parturients. Patients were assigned to receive either 20 mL of 0.5% racemic bupivacaine or 20 mL of 0.5% levobupivacaine, both with 10 microg sufentanil and epinephrine 1:200,000.
Results: Participated in this study 47 patients being 24 in the levobupivacaine group and 23 in the bupivacaine group. Both groups were comparable regarding maternal-fetal characteristics. Fifteen minutes after epidural anesthesia, 62.5% of levobupivacaine group patients experienced Bromage 2 or 3 motor block, whereas the same event was documented in 72.7% of bupivacaine group patients (p = 0.83). After 20 minutes, 66.7% of levobupivacaine group patients experienced Bromage 2 or 3 motor block versus 86.3% of bupivacaine group patients (p = 0.21). Most common complication was hypotension, detected in 16 (66.7%) levobupivacaine group patients and in 10 (43.5%) bupivacaine group patients (p = 0.11).
Conclusions: Levobupivacaine and bupivacaine were equally effective for epidural block in patients undergoing cesarean section.