Study to compare the effect of nalbuphine and butorphanol as an adjuvant to intrathecal 0.5% hyperbaric bupivacaine for lower limb surgery

Abstract

Introduction: Spinal Anaesthesia is routinely used for surgeries performed on lower abdomen, pelvis and lower limbs. Adjuvants allow multiple benefits, most significant being provision of post-operative analgesia. Aims: This observational study was conducted to compare intrathecal nalbuphine versus butorphanol with hyperbaric bupivacaine respectively to assess onset and duration of sensory and motor block, hemodynamic parameters, adverse drug reactions and duration of post-operative analgesia. Materials and Methods: Fifty participants between 20-60 years belonging to ASA grade I/II posted for elective surgery were assigned to : group BN (n=25) : Bupivacaine (0.5%) hyperbaric (3ml) + nalbuphine 1mg (0.1ml) + normal saline 0.1ml and group BB (n=25) : Bupivacaine (0.5%) hyperbaric (3ml) + butorphanol 200mcg (0.2ml). Mean period of sensory/motor blockade, hemodynamic parameters, adverse drug reactions and analgesic requirement post surgery were compared. Results: Onset of sensory blockade was comparable while onset of motor blockade was significantly earlier in nalbuphine than butorphanol. Duration of block and post-operative analgesia was significantly higher for nalbuphine. Hemodynamic parameters and adverse effects were comparable. Conclusion: Nalbuphine is more efficacious than butorphanol due to provision of early onset of motor blockade and prolonged period of sensory/motor blockade with delayed requirement of rescue analgesia.