[Parenteral nutrition: stability of lipid emulsions in different preparations]

We studied the stability of fat emulsions kept in plastic bags and mixed with different proportions of amino acids, glucose and divalent cations. The quantity of fat, vitamins and other electrolytes was kept constant. Visual examination, pH determination, and measurement of particle diameter in Coulter Counter was performed at 0, 24 and 84 h. Particles greater than 5 microns were detected only in mixtures with Ca++, Mg++ and Zn++ concentrations at or above 7.7, 13.3 and 23.4 mEq/l, respectively. We conclude that fat emulsions for parenteral nutrition remain stable in mixtures when the concentration of divalent cations is not unduly raised.