A double-blind prospective randomised controlled clinical study comparing 0.5% hyperbaric bupivacaine with nalbuphine and 0.5% hyperbaric bupivacaine for spinal anaesthesia in lower limb orthopaedic surgeries

Abstract

Background: Intrathecal nalbuphine is one such opioid, highly lipid soluble with an agonist action at the kappa and antagonist activity at the muopioid receptors, known cardiovascular stability, minimal dose and volume of this drug that can be added to a local anaesthetic agent.Methods: This prospective randomised double-blind study was conducted to evaluate the effects of adding nalbuphine to 0.5% hyperbaric bupivacaine in spinal anaesthesia to know the efficacy, duration of analgesia, incidence of side effects and complications. Sixty American Society of Anesthesiologists (ASA) grade I and II patients were randomly allocated to Group A and Group B of 30 each who received 0.4 mL (0.4 mg) of nalbuphine and 0.4 mL of normal saline added to 3 mL (15 mg) of 0.5% hyperbaric bupivacaine, respectively. Intraoperative haemodynamic parameters, onset, duration of sensory and motor block, visual analogue scale (VAS) score, duration of effective analgesia and possible side effects were monitored and compared.Results: There was no statistically significant difference in the haemodynamic parameters, onset of blockade, duration of motor blockade and side effects. However, in two-segment regression, time of sensory blockade, duration of effective analgesia and VAS scores in Group A were found statistically significantly higher (P < 0.001) compared to Group B.Conclusions: Intrathecal nalbuphine used as adjuvant to bupivacaine prolongs duration of effective analgesia, without any significant side effects with stable haemodynamic parameters.