Future trends in parenteral nutrition.

With our present knowledge of total, intravenous nutrition it is now possible to eliminate, or greatly reduce, the incidence of malnutrition, as a complication of various medical and surgical conditions in modern hospitals. There is a tendency to include supplementary or total intravenous nutrition in the feeding program of the hospital, to ensure that the patients get an adequate daily amount of nutrients. The trend in the development of intravenous nutrition is, to supply all nutrients in the same proportions as those in which they enter the general circulation following a well-balanced oral food intake. Various mixtures of amino acids have been used as part of a complete intravenous nutrition. All studies in this field indicate a trend to use those amino acids mixtures which contain the essential and the nonessential L-amino acids in the same proportions as are found in the aminogram of proteins with high biological value. There is a trend to include fat, as fat emulsion (soybean oil-egg yolk-phospholipid emulsion), for intravenous nutrition, in an amount corresponding to about 40 energy percent as both the source of energy and of essential fatty acids for the body. To make an intravenous nutrition as complete as possible, all essential minerals should be included. Phosphorus is of special interest here as it aids in the prevention of hypophatemia and tissue anoxia caused by deficiency of diphosphateglycerate in the erythrocytes. Zinc may also be mentioned because of its importance for wound healing. There is also a tendency to include all the 13 necessary vitamins in an intravenous feeding program. In this connection vitamin K1 is of special importance. If patients on intravenous nutrition are treated with antibiotics, this may result in a change in the intestinal flora and a loss of intestinal vitamin K production, causing vitamin K deficiency, with severe or fatal bleeding. Consequently, vitamin K1 should be given daily to every patient on intravenous alimentation. The future trend in parenteral nutrition will also be to use this method for exact nutrition balances. In this way it will be possible to determine the endogenous loss via feces, as well as to study the requirements of nutrients in different conditions.