Parenteral nutrition admixtures and drugs

The concept of parenteral nutrition admixture in a single container first appeared in 1974 in an article published by Cl. SOLASSOL et H. JOYEUX in Montpellier.

These admixtures mean that all the nutrients corresponding to the patient’s needs can be delivered continuously at a regular rate and through one single route. Until then, each nutrient was injected separately. This concept of nutrition admixture represented a major advance in clinical practice bringing improved patient comfort, reduced metabolic and infectious complications and optimal nutritional performance.

The main problem raised by these mixtures is that of their stability over time and of the numerous interactions among nutrients and between nutrients and drugs.

This presentation addresses the different types of instability and interactions reported in the literature. They may be of different kinds: stability of emulsion, chemical, physical or pharmacokinetic.

Several studies have demonstrated the effects of other nutrients on the stability of lipid emulsion and shown the mechanisms involved. The most destabilizing elements are divalent cations and dextrose.

Chemical and physical interactions with the nutrition admixture may be caused by some nutrients such as electrolytes or vitamins, and also by the addition of drugs in bags or Y-site infusion.

There are very few studies on the pharmacokinetic interactions caused by concomitant administration of lipids and drugs. We will take the example of amphotericine B.

Overall all these studies should be treated with care because of the multifactorial nature of the interactions. The composition of the nutrition admixtures, the concentrations of nutrients and drugs and the protocols used in the studies are the most important variables likely to cause contradictory results or results which cannot be extrapolated.

For this reason recommendations concerning the preparation, shelf life and routes of delivery are essential but difficult to establish.

The author declares that he has no conflict of interest with regard to the work presented.