WHOLE-BLOOD IONIZED MAGNESIUM IN THE HEALTHY NEONATE

Objective: We aimed to determine the normal range of ionized magnesium (IMg2+) concentration at birth and 24 hours of life in the healthy, t erm (37 to 41 weeks old) neonate. Methods: Cord blood was obtained fro m the umbilical vein of 30 patients. In addition, blood was obtained f rom 32 infants at 24 hours of life. Whole blood was analyzed to determ ine IMg2+ concentration, ionized calcium concentration, and pH. Result s: The normal range of IMg2+ concentration (mean +/- 2 SD) was found t o be 0.40 to 0.56 mmol/L (0.97 to 1.36 mg/dL) at both birth and 24 hou rs of life. Conclusions: The normal range of IMg2+ concentration (mean +/- 2 SD) in the healthy neonate at birth and 24 hours of life is 0.4 0 to 0.56 mmol/L (0.97 to 1.36 mg/dL). This range can serve as a refer ence value for future studies regarding the clinical usefulness of IMg 2+ concentration determination in neonatal disease states.