Efficacy of ropivacaine, bupivacaine, and levobupivacaine for labor epidural analgesia.

STUDY OBJECTIVE: To compare analgesic efficacy and intensity of motor block with continuous infusions of ropivacaine, bupivacaine, and levobupivacaine in combination with fentanyl for labor epidural analgesia.

DESIGN: Prospective, randomized, double-blinded study.

SETTING: Labor and delivery suite at Magee Womens Hospital, Pittsburgh, PA.

PATIENTS: 162 ASA physical status I and II, full-term, primiparous women.

INTERVENTIONS: All patients received epidural labor analgesia. Epidural medication consisted of an initial bolus of 8 mL local anesthetic with fentanyl (100 microg) followed by an infusion at 12 mL/h of local anesthetic with 2 microg/mL fentanyl. Patients were allocated to one of three groups, as follows: group 1 received bolus and infusion of bupivacaine 0.125%, group 2 received bolus and infusion of levobupivacaine 0.125%, and group 3 received a bolus of ropivacaine 0.2% and infusion of ropivacaine 0.1%.

MEASUREMENTS: Maternal vital signs, pain visual analog scale (VAS) score, sensory levels, and motor block (Bromage score) were recorded every hour. Duration of first and second stage of labor and mode of delivery were also recorded.

RESULTS: There were no statistically significant differences in pain VAS or Bromage motor scores among the three groups of patients at any of the measured time intervals. The time to achieve T10 sensory level and patient comfort was shorter in the ropivacaine (9.35 +/- 4.96 min) and levobupivacaine (9.56 +/- 4.71 min) groups than the bupivacaine (11.89 +/- 7.76 min) group, although this difference did not reach a statistically significant level (P = 0.06). The second stage was significantly shorter in the bupivacaine group, lasting 81.27 +/- 63.3 min, compared with the ropivacaine group (121.69 +/- 86.5 min) and the levobupivacaine (115.5 +/- 83.6 minutes) group (P = 0.04).

CONCLUSION: There are no significant differences in pain VAS and Bromage scores between 0.1% ropivacaine, 0.125% bupivacaine, and 0.1% levobupivacaine given for labor epidural analgesia.