A randomized, double-blind, controlled study comparing Bupivacaine 0.125% and Ropivacaine 0.125%, both with Fentanyl 2 μg/ml, for labor epidural analgesia

Abstract

Objective: A prospective, randomized, double-blind study was conducted to compare the efficacy of Ropivacaine 0.125% and Bupivacaine 0.125%, both with Fentanyl 2 microgm/ml, in labor epidural analgesia and their effect on duration and course of labor. Background: Ropivacaine was introduced as S-enantiomer. In various human and animal studies, it was found to be less cardiotoxic and has high sensory:motor differential blocking property. Both these characteristics are beneficial for labor epidural analgesia. Materials and Methods: Sixty pregnant women of ASA grade I and II, who were primigravida or multigravida, with singleton vertex presentation in established labor were randomly selected and divided into two groups of 30 each. Group R patients received Ropivacaine 0.125% with Fentanyl 2 μg/ml and group B patients received Bupivacaine 0.125% with Fentanyl 2 μg/ml as intermittent bolus doses epidurally. After taking consent from them, epidural catheter was placed in L2-3/3-4 space, followed by administration of study drugs given as top-up doses intermittently. Maternal heart rate, systolic blood pressure (SBP), Visual Analogue Scale (VAS) score, fetal heart rate (FHR), Bromage score, level of sensory analgesia, APGAR score at 1 and 5 min, and duration of labor were recorded. Results: The groups were similar in demographic attributes and obstetric variables. Ropivacaine showed no difference in the mean VAS scores and the quality of analgesia, as compared to Bupivacaine. At 20 min, all the patients in both groups were absolutely pain free with the VAS score of 0. No patient in group R developed motor block, whereas five patients in group B developed grade 2 (mild) motor block. APGAR scores were comparable in both the groups. Conclusion: We conclude that Ropivacaine is equipotent, produces less motor block, has no adverse effect on the course and duration of labor, and can be used safely.