Studies on calorie to nitrogen ratio for total parenteral nutrition

In this study, three calorie nitrogen ratios, 102:1, 163:1 and 204:1, were analyzed in 40 week long study periods in a total of approximately 22 stable patients without sepsis who required parenteral nutrition. A calorie to nitrogen ratio of 163:1 appeared to be most efficacious for nitrogen equilibrium in these patients studied. A calorie to nitrogen ratio of 102:1 was associated with weight loss and negative nitrogen balance. Conversely, increasing the calorie to nitrogen ratio to 204:1, at least for this group of patients, did not result in improved nitrogen retention. Different methods of calculation of nitrogen equilibrium are presented, depending upon the disease state and the method by which data analysis is carried out. The results suggest that different levels of nitrogen and caloric input as well as calorie to nitrogen ratio may be appropriate in different disease states.