Comparing the Effects of Intrathecal Buprenorphine versus Fentanyl as Adjuvant to Hyperbaric Ropivacaine in Lower Limb Surgeries

Background: Subarachnoid block is often the choice of anaesthesia for lower limb surgeries.  Hyperbaric Ropivacaine, a newer commercially available local anaesthetic preparation, offers  faster recovery and fewer cardiovascular effects than bupivacaine but has a shorter duration of action. To prolong anaesthesia and postoperative analgesia, opioids such as fentanyl and buprenor-phine are used as adjuvants to local anaesthetics.
Aim: This study aimed to compare the efficacy and safety of intrathecal buprenorphine versus fen-tanyl as adjuvants to hyperbaric ropivacaine in lower limb surgeries.
Material and Methods: A prospective, double-blinded, randomised controlled trial was carried out in 76 patients, aged 18–60 years, belonging to ASA I and II and scheduled for lower limb pro-cedures under subarachnoid block. Patients were randomly allocated into two groups: Group B was given 3 ml of 0.75% hyperbaric ropivacaine with 0.5 ml buprenorphine (150 mg), while Group F got the same dose of ropivacaine with 0.5 ml fentanyl (25 mg). Parameters assessed included onset,level, sensory and motor block duration, changes in the haemodynamics, postoperative analgesia, and side effects.
Results: Group F showed a significantly faster onset (p=<0.001) and time to reach maximum sensory level (p=<0.001). However, Group B had a significantly prolonged duration of sensory block and analgesia (p=<0.001). Group B demonstrated better haemodynamic stability, with fewer episodes of hypotension and bradycardia, though not statistically significant. Onset of motor block was faster, but duration was shorter in Group B. Minor side effects like pruritus and urinary reten-tion were more frequent in Group B.
Conclusion: Buprenorphine as an intrathecal adjuvant to hyperbaric ropivacaine provides superior postoperative analgesia, prolonged sensory block, and better hemodynamic stability than fentanyl, making it a preferable choice for lower limb surgeries.