A comparison of 0.0625% bupivacaine with fentanyl and 0.1% ropivacaine with fentanyl for continuous epidural labor analgesia

We compared the analgesic efficacy and the degree of motor block achieved w ith epidural infusion of 0.0625% bupivacaine (Group B) versus 0.1% ropivaca ine (Group R), both with 0.0002% fentanyl (2 mug/mL) in laboring patients. A prospective, double-blinded study was performed in 98 ASA physical status I-IT parturients who were divided randomly into two groups to receive eith er bupivacaine or ropivacaine after catheter location had been tested with an initial bolus of lidocaine and fentanyl. The infusion rate was 15 mL/h i n every case. When pain was perceived, 5-mL boluses of the assigned epidura l analgesic were administered every 10 min until analgesia was achieved. We recorded pain intensity, level of sensory block, degree of motor block, he modynamic variables, secondary effects, mode of delivery, neonatal outcome, and patient satisfaction. There were no statistically significant differen ces in any of the factors analyzed. Highly effective analgesia was achieved in both groups with a small incidence of motor block. These findings sugge st that bupivacaine may be more potent than ropivacaine.