Comparitive study of intrathecal ropivacaine –fentanyl and bupivacaine- fentanyl for lower limb orthopaedic surgeries

INTRODUCTION: Spinal Anaesthesia is the widely used method for lower limb orthopaedic surgeries, providing a faster onset and effective motor and sensory blockade. It is simple, easy to perform and has got a definite endpoint. Intrathecal bupivacaine is widely used in spinal anaesthesia over a long period of time. In this setting, a newer drug Ropivacaine has emerged, which is being widely used for epidural blocks and nerve plexus blocks. Ropivacaine has an improved safety profile over bupivacaine with respect to central nervous system and cardio toxic potential. Though ropivacaine is being used frequently, in epidural and nerve blocks, the literature regarding its use in intrathecal route is sparse. AIM OF THE STUDY: Intrathecal bupivacaine results in a longer duration of complete anaesthetic block than ropivacaine. Fentanyl used as an adjuvant may improve the quality of spinal block of ropivacaine, while maintaining its advantage of early motor recovery. The aim of the study was to compare the efficacy and safety of intrathecal ropivacaine‑fentanyl (RF) with bupivacaine‑fentanyl (BF) for lower limb orthopaedic surgeries. METHODS: In this Single Centered, Prospective, Randomized, Parallel group, Double – Blind study, sixty patients were randomly allocated to receive either intrathecal 15 mg of 0.5% ropivacaine with 25 mcg fentanyl (Group RF) or 15 mg of 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. Data analysis was done by using SPSS software and Sigma Stat 3.5 version (2012). RESULTS: Time to reach highest sensory level, complete motor block and two segment sensory regression time were comparable. The motor recovery to Bromage scale 1 was faster in Group RF. The haemodynamic stability was better in Group RF. Time duration of analgesia was prolonged in Group BF. CONCLUSION: Intrathecal RF provided satisfactory anaesthesia with Haemodynamic stability for lower limb orthopaedic surgeries. It provided a similar sensory but a shorter duration of motor block compared to BF, which is a desirable feature for early ambulation, voiding and physiotherapy