Significance Of Ionized Magnesium To Diagnose Mgnesium Levels In The Perioperative Period Of The Rheumatic Heart Disease

Objective: To investigate the change of blood ionized magnesium (IMg) in the perioperative period of the rheumatic heart disease and detect the diagnosis value of the ionized magnesium. Methods: We choiced randomly twenty rheumatic heart disease patients (RHD group) and twenty congenital heart disease patients (CHD group) in our department. Blood samples, which were collected from central vein in both groups at the defined time points: 24 hours before operation; after aortic cross-clamp removal; 2,6,24,48 hours after operation, were measured the concentrations of ionized magnesium, ionized calcium (ICa), serum magnesium and aldosterone. At the meantime, report the age, sex, weight, cardiopulmonary bypass time, aortic cross-clamp time, ventricular arrhythmias and the pharmacon use in perioperative period. Results: There was no demographic difference in sex and weight in two groups. However, the difference of age, cardiopulmonary bypass time, aortic cross-clamp time, ventricular arrhythmias after operation reached statisticalsignificance (p<0.05). There was no difference in serum magnesium in two groups 24 hours before operation while the ionized magnesium in RHD group 24 hours before operation was lower than that in CHD group (0.46±0.12mmol/L vs 0.59±0.13mmol/L, p<0.01). After the operation, the ionized magnesium levels of two groups all decresed, but the serum magnesium kept in normal levels. In RHD group, the ionized magnesium reached the lowest level (0.31±0.11mmol/L) 24 hours after operation. Before the operation, the concentration of aldosterone in RHD group was higher than that in CHD group, and reached the highest points 24 hours after the operation. In RHD group, after the aortic cross-clamp removal, the ICa/IMg in the patients with ventricular fibrillation was higher than that in the patients without ventricular fibrillation (2.17±0.08 vs 1.38±0.14, p<0.01). Conclusions: In rheumatic heart disease petients, the level of ionized magnesium was lower than normal while the serum magnesium was in normal level; After the operation, the ionized magnesium decreased singnificantly, but the concentrations of serum magnesium were in normal range. The aldosterone levels in RHD group were higher than those in CHD group. In RHD group, after the aortic cross-clamp removal, the ICa/IMg in the patients with ventricular fibrillation was higher.