Compatibility of calcium and sodium glycerophosphate in parenteral nutrition solutions

Abstract

Keywords: sodium glycerophosphate; calcium; phosphate; parenteral nutrition; neonate

Objectives: Preterm infants need high amounts of calcium and phosphorus for bone mineralization and growth, which is difficult to obtain with parenteral feeding due to its low solubility. The purpose of this study was to test the compatibility of sodium glycerophosphate (NaGP) with calcium gluconate in pediatric parenteral nutrition (PN) solutions.

Methods: Ten PN admixtures formulas for neonatal use were aseptically prepared. Standard formula consisted of 10%dextrose and 2%amino acid according to Ramathibodi Hospital pediatric PN prescription. In this study, calcium at the concentrations of 0, 20, 30 mmol/L and phosphate at the concentrations of 0, 20, 50 mmol/L, were orderly mixed into the standard formula. Each admixture separately tested according to 4 following conditions; after mixing, 30°C for 1 day, 4°C for 1 day and 4°C for 7 days. Visual inspections against a black and white contrast background, pH evaluation, spectrophotometry at 600 nm and particle size measurement were examined in triplicate.

Results: All testing parameters showed that PN solutions mixed with NaGP did not have any precipitation over 7-day storage duration. On the other hand, samples containing 50 mmol/L of inorganic phosphate and 30 mmol/L of calcium gluconate or inorganic phosphate and calcium gluconate 20 mmol/L equally of each, precipitations were obviously observed in PN admixtures.

Conclusion: NaGP showed no precipitation at all concentrations in PN admixtures used in this study. NaGP may be a good choice of phosphate source in PN preparation. However, further study was required to assess the safety, efficiency and cost-effectiveness of using NaGP in pediatric PN solutions.