Serum Magnesium Level in Critically Ill Children

Abstract

Introduction: Magnesium acts as a cofactor of more than 300 enzymes, particularly enzymes responsible for phosphate transfer, and regulates calcium ion movement in smooth muscle cells, which has an important role in maintaining cardiac contractility and peripheral vascular tone. Abnormalities in serum magnesium levels are known to cause life-threatening problems in critically ill children. Aim of the study: It aimed to investigate the serum magnesium level in critically ill children, identify precipitating factors that could affect the magnesium level, and conduct a prospective evaluation of the outcome. Subjects and Methods: 1 00 children were admitted to the ICU at Fayoum Teaching Hospital from March 1st, 2019 to November 30th, 2019. They were prospectively analyzed with the exclusion of children who received magnesium products within the last 24 hours and children with known congenital renal magnesium wasting (e.g., Bartter’s syndrome and Gitelaman’s syndrome). Results: The median magnesium level on admission was 2.5 (range 0.6-4.6) mg/dl. The percentage of hypomagnesaemia was 3% (3 cases), 57% (57 cases) had normal magnesium, and hyper-magnesaemia was present in 40% (40 cases) at admission. Serum magnesium levels were lower in non-survived children with a median of 2.3 (2.3-2.6) than in those who survived with a median of 2.5 (2.3-2.7), but there was no statistically significant association with mortality with a p value of 0.274. Conclusion: We can’t consider serum magnesium predictive of mortality. The incorporation of other electrolytes may be more predictive of mortality than magnesium.