Stability of amino acids, vitamins and trace elements in parenteral nutrition - Physicochemical risks and clinical practice recommendations

Abstract

The stability of amino acids, vitamins, and trace elements in parenteral nutrition (PN) admixtures is a critical factor in ensuring the safety, efficacy, and quality of intravenous nutritional support. This review analyzes the main degradation and instability mechanisms affecting these essential components, including the photooxidation of sensitive amino acids, Maillard reactions, the loss of water-soluble vitamins due to oxidation or interactions with trace elements, and the precipitation of micronutrients resulting from physicochemical incompatibilities. Key contributing factors such as pH, temperature, oxygen exposure, ultraviolet light, and packaging materials are described. The article integrates recent evidence and consensus recommendations, proposing practical strategies such as the use of multilayer bags, light protection, oxygen limitation, optimal sequence of component addition, physical separation of unstable compounds, and the use of in-line filtration during administration. These precautions are particularly important in vulnerable populations such as neonates or patients receiving long-term home PN. This consensus document aims to provide technical and clinical criteria to improve the safety and stability of nutrients administered parenterally, adapting their preparation and handling to real-world conditions in both hospital and home care settings.