Carbohydrates parenteral feeding

Infusion methods. The liberal use of the isotonic soy bean oil emulsion Intralipid ("Vitrum") in our parenteral feeding program reduces the resultant hypertonicity of the solutions. Intralipid and the solution containing amino acids, carbohydrates, electrolytes, etc., are infused simultaneously, the infusion sets being connected by a Y-piece. In most cases, such infusions can be made through peripheral veins (scalp and extremity veins) for several weeks. 

The principal energy sources in the diet are carbohydrates and fats. Glucose provides 4 kcal/g while fat provides 9 kcal/g. The entire calorie load may be admin-stered using carbohydrates, but prescribing a mixture of carbohydrates and lipids is more physiological and serves to reduce the volume of the diet. This is imponant in tube feeding as well as in parenteral nutrition. 

The effect of food on theophylline bioavailability is unclear. In general it appears that fat or fibre in food has no effect, whereas high-protein and high-carbohydrate diets decrease and increase the theophylline half-life, respectively. Significant changes in theophylline bio availability have been seen in patients given both enteral feeds and total parenteral nutrition. 

The use of L-amino acids constitutes part of the therapeutic measure of parenteral nutrition, which also includes fat emulsions and carbohydrates, i.e., sugars. Only with mixtures of amino acids is it possible to provide physiologic intravenous protein feeding. The modern use of intravenous amino acid nutrition was initiated by Elman (1937), following studies on casein hydrolyzates. 

Patients completely recover after replacement of oral feedings by total parenteral nutrition. A diet containing fructose as the only carbohydrate is well tolerated (hereditary fructose intolerance must be excluded). 

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