Comparison between 0.08% ropivacaine and 0.06% levobupivacaine for epidural analgesia during nulliparous labor: a retrospective study in a single center.

BACKGROUND Levobupivacaine and ropivacaine are new local anesthetics that have effects similar to bupivacaine. However, the relative potency of these two drugs is controversial. The purpose of this retrospective study was to assess whether a combination of 0.06% levobupivacaine and 0.0002% fentanyl had the same effects as 0.08% ropivacaine and 0.0002% fentanyl on the mode of delivery and other obstetric outcomes when used for epidural analgesia of labor in nulliparous women. METHODS Computer records of 392 Asian nulliparous parturients, who had presented with spontaneous labor or spontaneous rupture of the membranes, and had received epidural analgesia were retrospectively reviewed. Of these, 193 received 0.08% ropivacaine and 199 received 0.06% levobupivacaine. Fentanyl (0.0002%) was used in both regimens. RESULTS There were no significant differences in the mode of delivery, duration of labor, or neonatal outcome between the two groups. In the levobupivacaine group, the parturients required top-up boluses of local anesthetics more frequently (1.4 ± 1.6 vs. 0.9 ± 1.3, p< 0.0001), and the incidence of temporary maternal fever (25 % vs. 15%, p = 0.024) and the cost of local anesthetic were higher (292 ± 183 NTD vs. 146 ± 104 NTD, p< 0.0001). However, the amount of local anesthetic administered during labor was lower (79 ± 49 mg vs. 114 ± 81 mg, p< 0.0001) than for the ropivacaine group. CONCLUSIONS 0.06 % levobupivacaine was as effective as 0.08% ropivacaine, when both were used with 0.0002% fentanyl for labor epidural analgesia of nulliparous women.