To Evaluate the Effectiveness of Magnesium Sulphate as an Agent to induce Hypotensive Anaesthesia in Lumbar Spine Surgery. A Prospective Randomized, Placebo-Control Study

ABSTRACT

Introduction: This randomized placebo controlled study wasdesigned to evaluate the effectiveness of magnesium sulphateas an agent to induce hypotensive anaesthesia in lumbar spinesurgery.Material and Methods: The study included 100 patients ofboth sexes who were equally distributed in two groups, theGroup Mg(Magnesium sulphate group) and Group C (controlgroup). The Magnesium group received magnesium sulphate40mg/kg administered as a slow IV bolus over a period of 10minutes before induction and 15mg/kg/hr by continuous IVinfusion during surgery. The same volume of isotonic salinewas administered to the control group. Surgical time, heartrate and mean arterial blood pressure was measured.Results: In the magnesium group there was reduction insurgical time (103.54 mins vs 117.34 mins), although theanaesthestic time was 9 minutes longer in the Magnesiumgroup denoting a longer emergence time. The mean arterialpressure and heart rate were significantly reduced inMagnesium group(p<0.005). Postoperative shivering was alsoless in Magnesium group.Conclusion: Magnesium infusion resulted in a steady andsmooth reduction in mean blood pressure and reduced heartrate, with no episodes of severe hypotension. Furthermoremagnesium causes reduction in duration of surgical time andpostoperative shivering