A Pilot Study of the Efficacy of Intrathecal Neostigmine for Postoperative Analgesia in Lower Abdominal and Lower Limb Surgery at SIMS, Ghaziabad, Uttar Pradesh

Intrathecal neostigmine had been used in various doses to produce analgesia without neurotoxicity in both animal and human studies. The present study was conducted using 50µg intrathecal neostigmine methylsulphate with 12.5mg bupivacaine (0.5% heavy) for optimum duration of post-operative analgesia with minimal side effects. In this study 100 patients belonging to ASA physical status I and II, age 20–70 years of either sex scheduled for elective lower abdominal and lower limb surgeries under spinal anaesthesia were included. Patients were randomly allocated in two groups: group I (n=50, control) received 2.5ml bupivacaine + 0.5ml of normal saline and group II (n=50, test) received 2.5ml bupivacaine +0.5ml of neostigmine (50µg). Time of onset of sensory and motor block, highest level of block, duration of analgesia and side effects like hypotension, bradycardia, nausea, vomiting, etc were recorded. Onset time of sensory and motor block was much faster In bupivacaine and neostigmine group as compared to bupivacaine group. Patients were pain free for average 6–7 hours with bupivacaine and neostigmine as compared to 3–4 hours with bupivacaine. It was concluded that intrathecal neostigmine in the dose of 50µg provide post-operative analgesia for a period of 6–8 hours with lesser incidence of side effects of nausea and vomiting.