Background and Goal of Study: According to contemporary guidelines for good clinical practice (GCP), the initial pharmacological treatment of arterial hypertension may include any of the five classes of leading antihypertensive drugs. Magnesium, acting as natural calcium-channel blocker, induces direct and indirect vasodilatation thus playing a role in treatment of arterial hypertension.
Materials and Methods: In this double blind, prospective, randomized and controlled clinical trial, we assessed the effects of magnesium sulphate on cardiovascular stability in patients undergoing diverse planned surgical procedures under general balanced anaesthesia, who are diagnosed with arterial hypertension Grade 1 and 2. The research encompassed 100 patients of both sexes, aged from 20 to 65. Immediately before induction of anaesthesia with propofol, the patients received 30 mg/kg bolus doses and magnesium sulphate infusion at 10 mg/kg/h (M group, n=50) or saline placebo (K group, n=50). Anaesthesia was achieved and maintained with sevoflurane, fentanyl and rokuronium. Throughout the procedure, the following parameters were monitored and recorded: hemodynamic parameters, incidence of postoperative shivering, nausea and vomiting, time to waking up from anaesthesia, and pain intensity after waking up from anaesthesia.
Results and Discussion: Statistical analysis of categorized values of median arterial blood pressure (MAP) and heart rate (HR) revealed statistically significant difference between the groups in 60th and 90th minute of anaesthesia. MAP values were within the range of hemodynamic stability (-20% to 20% decline from basal values) in 21 patients from group K (42%) and in 38 patients from group M (76%). HR values were within the interval from -30% to 30% decline from basal values in 26 patients from group K (52%) and in 37 patients from group M (74%). Furthermore, lower incidence of postoperative shivering, nausea and vomiting was noticed in patients from group M.
Conclusion(s): We can conclude that magnesium sulphate as an adjuvant to anaesthesia reduces hemodynamic changes during anaesthesia and lowers the incidence of postoperative shivering, nausea and vomiting, yet not affecting the wake-up time after anaesthesia or pain intensity during the immediate postoperative period.
1. Houston M. The role of magnesium in hypertension and cardiovascular disease. J Clin Hypertens 2011;13(11):843-7.