Abstract 1058
Although hypermagnesemia is commonly seen immediately after birth in infants born to mothers receiving magnesium sulfate, late onset marked hypermagnesemia, especially in the absence of renal failure, is almost always iatrogenic. We report two cases of magnesium toxicity associated with total parenteral nutrition (TPN) infusion. Both infants were transferred from the same referring hospital one week apart with acute onset of shock, bradycardia and marked hypotonia initially thought to be septic shock. However, complete blood counts were not suggestive of infection and cultures were negative (Table) Infant A was diagnosed by retrospectively analysing serum magnesium and did not receive exchange transfusion. Infant B received 3 double volume exchange transfusions in the first 24 hours of admission. Serum magnesium returned to normal in 10 days for patient A and 7 days for patient B. Both infants are currently neurologically normal with normal EEG. A search for the magnesium source revealed a TPN solution in patient B that had 500 mEq/liter of magnesium. Further investigation revealed the pharmacy compounder circuit used to make the TPN solution had just been used to make adult magnesium solutions. Failure to flush the circuit would result in a magnesium contamination of the first TPN bag equal to that seen. In summary, we present symptoms and recovery from magnesium levels higher than ever reported in the literature. Further the source of the error is one of concern for any hospital making pediatric and adult intravenous solutions on the same machine. Finally, the outcome, despite the catastrophic presentation, appears at present to be normal, although further follow-up is planned.
