Nutritional support of the acutely ill patient

Administration of nutritional support in acutely ill patients can be seen as a balance between the need to provide nutrients and the known complications associated with infusions of each of the three major nutrients--glucose, fat, and protein. It is prudent to maintain calorie intake within reasonable limits. If facilities for measurements of O2 consumption and hence metabolic rate are available, these should be utilized. Otherwise, metabolic rate should be estimated. In patients who are in satisfactory nutritional condition and who are being nourished to preserve lean body mass, diets designed to maintain body cell mass should be utilized. Practically speaking this means an energy intake of 1.0 to 1.2 times the daily energy expenditure and an N intake of 200 to 300 mg/kg/day. In patients where the goal is restoration of lean body tissue, a nutritional regimen designed to achieve a positive calorie and N balance should be used. This generally means an energy intake of 1.4 to 1.6 times the energy expenditure, with a N intake of 250 to 400 mg/kg/day. The nonprotein calories are administered as 50% glucose and 50% fat. These recommendations are based on studies performed to data. The area of nutritional support of the acutely ill patient is under extensive investigation. It is likely that as more data are collected, these guidelines will be revised.