Background: The provision of high amounts of calcium and phosphate in parenteral nutrition (PN) solution for neonates is important for bone mass accretion. Because of the risk of calcium phosphate precipitation, a well-documented incompatibility for inorganic salts, the concentrations of these electrolytes in PN are generally limited to 5 mmol/L. The aim of this study was to assess the risk of precipitation of calcium phosphate when organic calcium and phosphate salts are used instead of inorganic salts.
Methods: Precipitation curves were determined for inorganic and organic calcium and phosphate salts in a PN solution favorable to precipitation (low concentration of amino acids and glucose) using visual inspection and particle counts.
Results: The use of organic phosphate salt was associated with a decreased risk of precipitation of calcium phosphate. No precipitation occurred up to a concentration of 50 mmol/L of calcium and phosphate. In contrast, organic calcium salt only slightly decreased the risk of precipitation.
Conclusion: Up to 50 mmol/L of organic calcium and phosphate salts can be safely mixed in PN, even in unstable conditions, making it possible to follow the current European recommendations for requirements in neonates.