Total and ionized serum magnesium and calcium levels during magnesium sulfate administration for preterm labor

Intravenous infusion of magnesium sulfate is not associated with cardiovascular, liver, kidney, and metabolic toxicity in adults

BACKGROUND

Magnesium (Mg) deficiency contributes to the pathophysiology of numerous diseases. The therapeutic use of Mg has steadily increased over time. The increased in-hospital use of intravenous (IV) magnesium sulfate (MgSO4) warrants more extensive investigation regarding the safety of the therapy. The aim of this study was to determine the safety of IV MgSO4 infusion on cardiovascular, liver, kidney, and metabolic markers in adults.

METHODS

Twelve volunteers were randomized to one of two cross-over conditions: (a) IV infusion of MgSO4 in 5% dextrose followed by IV infusion of 5% dextrose 1 week later or (b) IV infusion of 5% dextrose followed by IV infusion of MgSO4 in 5% dextrose 1 week later. An electrocardiogram was recorded continuously during the infusions. Blood was drawn pre- and post-infusion for blood count (high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides). Results: Serum Mg increased from pre- to post-infusion in the MgSO4 + 5% dextrose group (p < 0.0001). The QRS interval length increased from pre- to post-infusion in the MgSO4 + 5% dextrose group (p < 0.04). Additionally, serum glucose concentration increased in the MgSO4 + 5% dextrose group (p = 0.04). These significant findings were modeled with gender and age as covariates. No other significant differences were found.

CONCLUSIONS

The administration of IV infusion of MgSO4 (4 g/100 mL) in 5% dextrose over a 4-hour treatment period poses no significant deleterious effects on cardiovascular, liver, kidney, or metabolic function.

RELEVANCE FOR PATIENTS

IV infusion of MgSO4 may be used for certain treatment indications without significant concern for systemic or organ toxicity.