Past, present, and future of nutritional support

Early rudimentary attempts to provide adequate nutrition by mouth, intestinal tube, and vein in order to reduce morbidity and mortality have advanced to strategies designed to maintain the integrity of the body cell mass. Technology has progressed geometrically in recent years with the development of organ-specific enteral and parenteral substrate mixtures; sophisticated assessment, delivery, and monitoring systems; and improved safety and efficacy. Nutritional support is rapidly evolving into the practice of clinical biochemistry, in which nutrient substrates will be formulated to enhance or maximize cellular function, not only under normal conditions, but under a wide variety of pathophysiologic conditions.