Calcium and phosphate solubility curves for parenteral nutrient solutions containing Vaminolact

Calcium and phosphate incompatibility in the total parenteral nutrient (TPN) solutions is a common problem especially in neonates. Their combinations in TPN admixture must be tested before use. We here investigated the compatibility of calcium and phosphate in TPN solutions containing a newborn amino acid product, Vaminolact. The TPN test-solutions contained 10 per cent dextrose, 1, 2, or 3 per cent Vaminolact, 4 mmole/L of magnesium sulphate and various combinations of calcium gluconate and dipotassium phosphate. Precipitations and crystallizations were inspected visually and microscopically after 24 hours standing at room temperature. Solubility curves were made by plotting the maximum concentrations of calcium and phosphate at which both were still compatible in the solution. Such curves are extremely helpful for clinicians and pharmacists to administer maximum calcium and phosphate dose for individual patient requirement.