Effectivness of dexametasone vs. Magnesium sulphate in postoperative analgesia: Dexametasone vs. Magnesium sulphate

Abstract

Introduction: Preoperative use of additive substances may be very helpful in perioperative acute pain management. Intravenous administration of dexametasone in preoperative period prevents postoperative nausea and vomiting but also provides better pain relief. It is also well known that magnesium sulphate (the NMDA receptor's antagonist) by its central mechanism of action may be effective in postoperative pain control. Aim: The purpose of this study was to evaluate the effect of dexametasone and magnesium sulphate on postoperative pain management in patients undergoing abdominal surgery (open cholecystectomy). Methods: Seventy eight patients scheduled for elective surgery (open cholecystectomy) were included in this study. This was the prospective cohort randomized placebo- controlled study. A total of 78 patients were randomized into three groups. Each group had twenty six patients. The group D, received dexametasone 0.1 mg/ kg iv 30 minutes before surgery. The group M received magnesium sulphate 3 mg/kg iv 30 minutes before surgery. The third group S was placebo group and patients in this group received saline in the same volume for each patient. For pain control after surgery all patients received tramadol 0.9-1.2 mg/kg and diklophenac 1.76 mg/kg. When necessary (VAS ≥ 7), morphine sulphate in dose 0.15 mg/kg was administred subcutaneously For treatment of emetic episodes metoclopramid 10 mg iv. was used. The patients were observed for intensity of pain measured VAS 0-10, pain relief and satisfaction with therapy, sedation, adverse events, emetic episodes and hemodynamic parameters. Results: There was no difference between groups regarding demographic data (age, gender, body weight), ASA score, comorbidity, duration of surgery and anesthesia and amount of fentanyl received during surgery. In group D 11.54% of patients received additional analgesia (morphine sulphate 0.15 mg/kg sc) in the first 4 hours and 27% of patients in the first 24 hours postoperatively. In group M 38.45% of patients received additional analgesia in the first 4 hours and total of 53.8% of patients in the first 24 hours. In placebo group only 2 patients did not require additional analgesia. There was significant statistic difference between groups in morphine consumption in the first 24 hours postoperatively (p < 0.01). There was no side effects. Conclusion: Dexametasone and magnesium sulphate given intravenously in preoperative period (30 minutes before surgery) improved pain control in first 24 hour postoperatively. Dexametasone administered alone provided faster onset and better pain relief including prevention PONV compare with magnesium sulphate iv. There was no side effect of this therapy.

Keywords

• magnesium
• dexametasone
• postoperative pain management