Comparison of intrathecal ropivacaine-fentanyl and bupivacaine-fentanyl for major lower limb orthopaedic surgery: A randomised double-blind study.

BACKGROUND AND AIMS: Intrathecal bupivacaine results in complete anaesthetic block of longer duration than ropivacaine. Fentanyl as an adjuvant may improve the quality of spinal block of ropivacaine while maintaining its advantage of early motor recovery. In this study, we proposed to compare the efficacy and safety of intrathecal ropivacaine-fentanyl (RF) with bupivacaine-fentanyl (BF) for major lower limb orthopaedic surgeries.

METHODS: Sixty patients were randomly allocated to receive either intrathecal 15 mg 0.5% ropivacaine with 25 mcg fentanyl (Group RF) or 15 mg 0.5% bupivacaine with 25 mcg fentanyl (Group BF). The onset, duration, spread of sensory and motor block, haemodynamic parameters and side effects were recorded. Statistical Package for Social Sciences 20 software was used for statistical analysis.

RESULTS: Time to reach highest sensory level and complete motor block were comparable. Sensory regression to L1 dermatome was 226 ± 46.98 min in Group RF and 229.33 ± 50.51 min in Group BF, P = 0.36. The motor recovery to Bromage scale 1 was faster in Group RF (242.8 ± 47.06 min) than Group BF (268 ± 49.9 min) P = 0.023. Time for rescue analgesia was prolonged in Group BF (263.33 ± 63 min) when compared to Group RF (234.44 ± 58.76 min), P = 0.021. The haemodynamic stability was better in Group RF than Group BF.

CONCLUSION: Intrathecal RF provided satisfactory anaesthesia with haemodynamic stability for major lower limb orthopaedic surgery. It provided similar sensory but shorter duration of motor block compared to BF which is a desirable feature for early ambulation, voiding and physiotherapy.