The photodegradation of vitamins A and E in parenteral nutrition mixtures during infusion.

BACKGROUND & AIMS: Vitamins A and E are the most light-sensitive vitamins. Vitamin A is degraded by photolysis, while vitamin E degrades by photo-oxidation. The composition of the parenteral nutrition mixture and the container could therefore influence degradation during daylight administration. The aim of this study was therefore to determine the influence of fat emulsion and the type of bag on the photo-degradation of vitamins A and E in Parenteral Nutrition (PN) mixtures during simulated infusion in daylight.

METHODS

Representative adult PN mixtures, with and without fat emulsion, were prepared. Samples for analysis were taken from infusates and each bag during simulated infusion. Degradation of vitamins A and E was determined by stability-indicating HPLC analysis.

RESULTS

Results indicated that vitamin A loss proceeded rapidly during infusion, resulting in up to 80% loss in 6 hours, even with light protection of the bag. The presence of fat emulsion did not provide significant light protection. Vitamin E degradation was substantial if mixtures were prepared in EVA bags but was largely prevented if PN mixtures were compounded and stored in multi-layered bags.

CONCLUSIONS

It is recommended that all PN bags should be light-protected during infusion in daylight. The use of multi-layered bags will prevent vitamin E losses during infusion.