Comparative study of intrathecal isobaric ropivacaine versus hyperbaric bupivacaine for cesarean section

Abstract

Introduction: Hyperbaric bupivacaine is widely used local anesthetic for cesarean section under subarachnoid block, but it has longer duration of motor block. Ropivacaine has shown greater selectivity for sensory blockade along with lower systemic toxicity compared to bupivacaine when used for spinal anesthesia. Our aim was to compare efficacy of intrathecal 0.75% isobaric ropivacaine with 0.5% heavy bupivacaine for cesarean section.

Methodology: In this randomized, blinded study, sixty four American Society of Anesthesiology (ASA) II patients for cesarean section were allocated to receive either intrathecal 21mg 0.75% ropivacaine(R) or 11mg 0.5% bupivacaine(B). Onset, duration, spread of sensory and motor block, haemodynamic parameters and side effects were recorded.

Results: Time to achieve sensory block to T6(R:5.2±1.5vsB:3.3±1.0 minutes) and to maximal level (R:6.3±1.7vsB:3.9 ±1.2 minutes) were longer in ropivacaine group (p<0.001). Duration of sensory block was comparable in both groups(R:136.5 ± 17.7 vsB:140± 20.3 minutes). Duration of motor block was significantly shorter than bupivacaine group(R:131.5±17. 4vsB:152.3±14.7) (p<0.001).

Conclusion: Spinal anesthesia for cesarean section with intrathecal 21 mg of 0.75% isobaric ropivacaine provided clinically effective surgical anesthesia with similar sensory block but shorter duration of motor block. sickness in either the children or their parents.