The metabolic response to injury and illness as manifested by increases in energy expenditure and nitrogen losses makes it difficult for the clinician to evaluate calorie and protein needs. A method for determining daily calorie needs in hospitalized patients is presented. Average increases in resting metabolic expenditure for a group of patients following elective operation, skeletal trauma, skeletal trauma with head injury, blunt trauma, sepsis and burns were determined by indirect calorimetry and protein need by urinary nitrogen losses over extended time periods. Total daily calorie needs were then calculated, using the Harris-Benedict equation and adjusting this value upward using a previously measured activity and injury factor to arrive at the daily needs. Protein requirements may be determined on periodic 24 hour urine samples analyzed for the urinary urea nitrogen and adjusting this to a total nitrogen or protein equivalent. This approach to estimating the calorie nitrogen needs of the hospitalized patient under various degrees of stress more closely approximates the patient's variable needs at the height of the catabolic response and during convalescence.

No abstract

The moisture contents of foods, fluids, and parenteral solutions taken in and of all samples excreted, the water of oxidation of fuel mixtures burned, and the evaporative water loss must be determined in order to obtain a quantitative picture of water balance. Because there is a tendency to retain water after trauma, surgery, or an acute illness, changes in the water compartment of the body may lead to changes in body weight that may be considered erroneously as changes in energy or protein stores. Measurement of water balance, in addition to calorie and nitrogen balance is one of the most accurate means of accounting for these changes in body composition. Fluid and electrolyte therapy and nutritional supplementation can be tailored to meet the patient's specific needs by utilizing this information. Application of these principles to the care of hospitalized patients outside of the research setting will be discussed.