STABILITY OF VITAMINS IN SOYBEAN OIL FAT EMULSION UNDER CONDITIONS SIMULATING INTRAVENOUS-FEEDING OF NEONATES AND CHILDREN

The stability of the fat-soluble vitamins and thiamine, riboflavin, pyridoxine, ascorbate, and folic acid when administered as part of Intralipid 10% was evaluated. Intravenous pediatric vitamin formulations (Vitalipid N Infant and Soluvit Infant) containing the daily dose for term neonates were diluted with Intralipid to final volumes of 12.5 mL or 260 mL. The volumes were then delivered for 24 hours via dihexylethyl-phtalate-free in vitro infusion systems that simulated clinical conditions. The first vitamin-Intralipid admixture (12.5-mL volumes) was pumped (by syringe) during 24 hours through neonatal infusion sets placed in an incubator (37 +/-1-degrees-C, bilirubin light). Aliquots were collected at the beginning of the experiment and after 24 hours of infusion. The second admixture (260-mL volumes) was pumped (by a peristaltic pump) through infusion sets during 24 hours and was exposed to periodic indirect sunlight and to continuous fluorescent light to simulate the feeding of a child. Aliquots were collected at 0, 8, and 24 hours during administration of the The vitamin concentrations were measured by high-performance liquid chromatography. The effect of the vitamins on the stability of the emulsion was also assessed by visual inspection, lipid globule size distribution, and pH change. Losses of vitamins vary from different experimental conditions and were for the fat-soluble vitamins essentially nil, except for phylloquinone, which was 5% to 17% below the initial level. Thiamine, pyridoxine, and folic acid were stable. Losses of riboflavin and ascorbate amounted to 10% to 20% and 9% to 52%, respectively. These results demonstrate that the vitamin stability is good when vitamins are administered in a vitamin-Intralipid admixture. The addition of vitamins to Intralipid did not alter the stability of the fat emulsion for up to 24 hours at room temperature.