The Effect of Perioperative Magnesium Sulfate on Blood Sugar in Patients with Diabetes Mellitus Undergoing Cardiac Surgery: A Double-Blinded Randomized Study

OBJECTIVE: The aim of the present study was to evaluate the perioperative effect of magnesium infusion on blood sugar level in patients with diabetes mellitus undergoing cardiac surgery. DESIGN: This was a double-blind randomized study. SETTING: The study was conducted at cardiac center. PATIENTS: The study included 122 adult patients. INTERVENTION: Group M – The patients received a continuous infusion of magnesium sulfate (without a loading dose) at 15 mg/kg/h. The infusion rate was started 20 min before induction maintained during surgery and the first postoperative 24 h. The medication was prepared by adding 5 g magnesium sulfate in 50 ml syringe. Group C – The patients received equal amount of normal saline. MEASUREMENTS: The monitors included heart rate, mean arterial blood pressure, central venous pressure, urine output, blood levels of magnesium, sugar, and potassium. RESULTS: The blood sugar level and the required insulin significantly decreased with Group M than Group C (P < 0.05). There were minimal changes in the potassium level in Group M, but potassium decreased in patients of Group C (P < 0.05). The amount of urine output was too much higher in Group M than Group C (P < 0.05). The pharmacological and mechanical support significantly decreased with Group M than Group C (P < 0.05). The hospital and Intensive Care Unit length of stay significantly decreased with Group M than Group C (P < 0.05). CONCLUSION: The magnesium sulfate produced a better-controlled effect on the blood sugar level. It decreased the requirement of insulin infusion and minimized the changes in the blood level of potassium.