ABSTRACT
This randomized, double-blinded, prospective study was aimed to evaluate and compare the analgesic effect of Magnesium and lidocaine on pain, analgesic requirements, quality of sleep and bowel function in patients undergoing laparoscopic cholecystectomy. Seventy five patients were assigned into three groups [n=25 each]. Group M received magnesium sulphate 50 mg kg[-1] as a bolus dose followed by 25 mg Kg[-1] h[-1] Group L received lidocaine 2 mg kg[-1] as a bolus dose followed by 2 mg kg[-1] h[-1] and those of placebo group received saline infusion in an equal manner. These regimens were started 30 minutes before induction of anaesthesia and were discontinued at the end of surgery. Intraoperative fentanyl, cisatracurium and average end tidal sevoflurane were calculated. Pain scores at rest and upon cough and movement were evaluated 1, 2, 6, 12 and 24 h after surgery. Postoperative morphine consumption were recorded at 2 and 24 h. Time to first flatus and insomnia were evaluated after 24 hours. Magnesuim and lidocaine infusions alter anaesthetic dose requirements. Patients in the Magnesim and lidocaine groups had better pain relief and lower opioid consumption than the placebo group [p<0.001]. In addition, lidocaine was associated with earlier return of bowel function and magnesium caused a better quality of sleep [p<0.05]. Both lidocaine and magnesium reduced intraoperative anaesthetic requirements and improved the quality of postoperative analgesia. Moreover, their opioidsaring effect was maintained in the early postoperative period and after 24 hours during the first postoperative day