Combination of GIK and Magnesium as a Solution of Choice to Protect Myocardium in High-Risk CABG

Background- CABG is one of the most common surgical procedures, especially among heart surgeries. Protection of the myocardium during and after the early stages of operation has special importance. Different medical and drug techniques have been used for this purpose. One of these techniques is infusion of glucose-insulin-potassium (GIK) solution. We compared the efficacy of GIK solution and GIK- magnesium (Mg) in two groups. The first group received GIK solution without Mg and the second group GIK plus Mg solution, to protect the function of the myocardium. Method- In a double-blind randomized study, we selected 50 patients as candidates for CABG with left ventricular ejection fraction (LVEF) less than 30% and without any severe lung, kidney and blood diseases. These 50 patients were divided in two equal groups. After induction of anesthesia with the same method for both groups, we infused 10 ml/hr GIK in the first group and the same amount of GIK-Mg in the second group for 10 hours in each group and the length of the time and the amount of solution were equal and also stages of induction and maintenance of anesthesia in both groups were similar. We studied vital signs, hemodynamic parameters and complications in both groups during induction, cardiopulmonary bypass (CPB), during stages of weaning these patients from CPB, during their stay in the ICU and until discharge from the hospital. Results- Complications such as sudden fibrillation, arrhythmias, ST elevation during weaning the patients from CPB, intubation time and stay in hospital and ICU in the GIK-Mg group were significantly less than the GIK without Mg group. More importantly, the average percentage of LVEF on discharge in the GIK-Mg group was higher than the group without Mg solution. Discussion- Our study demonstrated that infusion of GIK-Mg is more effective in protection of myocardial function and decreasing complications in CABG patients with LVEF less than 30% than GIK without Mg solution. So, it is recommended that in such patients, GIK-Mg solution should be used routinely (Iranian Heart Journal 2005; 6 (3): 15-21).