Metabolic Requirements of the Critically Ill, Mechanically Ventilated Trauma Patient: Measured Versus Predicted Energy Expenditure

Nutritional requirements of mechanically ventilated, critically ill trauma patients are to estimate because of the variety of injuries and many variables that must be considered in making an accurate nutrition assessment. The Harris‐Benedict predictive equation is often cited in the literature as an overestimation of caloric requirements in the critically ill when compared with indirect calorimetry, and, additionally, studies examining critically ill populations are inconsistent with the application of two important variables: physical activity and fasting. For this study, measurements of resting energy expenditure were compared with the predicted basal energy expenditure (BEE) using the Harris‐Benedict equation with the addition of a selected injury correction factor (ICF), and potential relationships were evaluated for their agreement. When the elements of routine intensive care unit physical activity (which increases energy expenditure by approximately 10%) and the patient's fasting state (the specific dynamic action of food which increased energy expenditure by 10%) are accounted for by the addition of 20% to the measured resting energy expenditure (MREE), the predicted BEE with ICF was in moderate significant agreement with MREE.