Background: Post-operative pain is the major morbidity of most of the surgeries. This prospective  single-blind, randomized, placebo controlled clinical trial was designed to evaluate the effect of Pre-operative IV Magnesium sulphate on Intraoperative and Postoperative pain management and to determine the adverse reactions, as it blocks N-Methyl D Aspartate receptor, among the patients undergoing elective abdominal surgeries  under general anaesthesia.

Patients and Methods: This study included 80 adult male and female patients, ASA physical status I and II, undergoing various abdominal surgeries under general anesthesia. Patients were randomly allocated into 2 equal groups. Patients in group M and C each group comprising of 40 patients each.

Group M (MAGNESIUM):  Subjects were given Magnesium sulphate 40 mg/kg 100 ml of.9% normal saline over 15 minutes prior to induction

GROUP C (CONTROL): Subjects were given 100ml of.9% normal saline plain over 15 minutes prior to induction.

Results: Results showed that total consumptions of Fentanyl, Atracurium and Tramadol in group M was 155.25 ± 42.61, 50.50 ± 6.77 and 5.0 ± 15.19  mcgm and in group C was 223.75 ± 25.49, 64.50 ± 5.97 and 46.25 ± 13.3 µg P value <.001. (P <0.05. Recovery time was significantly shorter (P <0.05) in magnesium group. Postoperative pain score as well as total analgesic requirement was significantly lower (P < 0.05) in magnesium group compared to control group.

Conclusion: In conclusion, this study suggests that on giving magnesium sulphate 40 mgm/kg bodyweight prior to induction provides good quality of analgesia, reduces opioid consumption both intraoperatively and post operatively and decreased need for rescue analgesic post operatively. In addition magnesium sulphate decreases the requirement of neuromuscular blocking agents, without delaying emergence from anaesthesia.

Keywords: Low Dose, Magnesium sulfate; abdominal Surgeries; Anesthesia; post op Analgesia.

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Dr Wasim Rafiq

Sr. Resident, Department of Anesthesiology & Critical Care, Govt. Medical College, Srinagar, India

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