A Comparative Study of Two Different Doses of Epidural Neostigmine Coadministered with Lignocaine for Post Operative Analgesia and Sedation

BACKGROUND: Adjuvants have been used to prolong analgesic effects of epidural local anaesthetics. We studied two different doses of neostigmine. PATIENTS & METHODS: A randomized double blind study was conducted on ninety adult females scheduled for lower intra abdominal surgeries. The study was designed to compare two doses of epidural neostigmine co administered with lignocaine, with regard to its analgesic efficacy and its effect on sedation in postoperative period. Patients were divided into three groups of 30 each. Group I received lignocaine 1% (9ml) with normal saline (1ml), group II lignocaine1% (9ml) with neostigmine 100μg in saline (1ml) and group III received lignocaine 1% (9ml) with neostigmine 200μg in NS (1ml). Group I served as a control. In operating room, after putting epidural catheter, general anesthesia was administered with propofol (2mg kg(-1)), succinylcholine (2mg kg(-1)) and maintained with O2, N2O, relaxant technique. At the end of surgery, patients were reversed. Epidural analgesic medication was administered to after proper recovery from anesthesia. Intensity of pain relief on VAS, duration of analgesia, level of sensory block, motor blockade, sedation by sedation score and complications were assessed. RESULTS: The addition of neostigmine resulted in significant longer duration of analgesia (dose independent) and sedation (dose dependent). Sensory and motor blockade were identical in all three groups. There was no incidence of respiratory depression, pruritus, bradycardia or hypotension in any group. Two patients in control group and one, receiving neostigmine (200μg), developed nausea/vomiting. CONCLUSION: Co administration of epidural neostigmine and lignocaine appears to be a useful technique for postoperative analgesia as it increases the duration of analgesia and provides desirable sedation at the same time.