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LEARNING OUTCOME: To examine the accuracy of predictive formulae compared to indirect calorimetry for determining energy requirements in critically ill, obese patients. Energy requirements are difficult to predict in critically ill, obese patients due to an increased resting energy expenditure compared to lean counterparts also compounded by the stressors of illness. The accuracy of predictive formulae is crucial as determination of energy expenditure by indirect calorimetry is not always possible. A retrospective review of patients receiving parenteral or enteral nutrition during 1993–1995 identified 57 obese patients [25 ventilator dependent (V), 32 spontaneous breathing (S)] with body mass index 30-50kg/m2. To evaluate the accuracy of predictive formulae compared to measured resting energy expenditure (MREE) by Deltatrac Metabolic Monitor the limits of agreement analysis was used to determine the bias (the mean difference between measured and predicted values) and the precision (the standard deviation of the bias). Predictive accuracy of formulae within ±10% MREE were also determined . The predictive formulae examined were: the Harris-Benedict equations (HBE) using actual weight, without a stress factor and with a stress factor of 1.3; HBE using the average of actual and ideal weights, without a stress factor and with a stress factor of 1.3; the Ireton-Jones equations for obesity and hospitalized patients (S,V); and the ratio of 21kcal / kg. The adjusted average weight Harris-Benedict equations were optimal for predicting MREE for the combined S and V set (bias = 182±123; 67% ±10% MREE), as well as the S subset (bias = 159±112; 69% ±10% MREE). Accurate prediction of MREE required adjustment of the average weight HBE with a stress factor of 1.3. The mean MREE was 21kcal / kg. The absolute value is recommended for use in limits of agreement analysis. Predictive formulae were least accurate for the V subset, therefore indirect calorimetry measurement is recommended for obese, ventilator dependent patients.

There is no single available measurement for evaluating the short-term response to nutrition therapy. The ideal parameter should have high sensitivity and specificity and should be unaffected by non-nutritional factors. A literature review suggested that plasma retinol-binding protein and prealbumin concentrations change earlier than albumin and transferrin levels and appear to correlate better with nitrogen balance during nutrition therapy. That conclusion was supported by our own findings in patients receiving total parenteral nutrition and following the transition to oral or enteral feedings. Although concentrations of these plasma proteins have been shown to be affected by stress and renal and hepatic disease, they appear to be more sensitive indicators of the adequacy of nutrition support than other more commonly used assessment parameters. J Am Diet Assoc 89:684-687, 1989.

The purpose of this study was to identify the research activites that were part of dietetic internship and coordinated undergraduate programs. Data about required research courses, research-related experiences, curriculum competencies, student publications, and faculty needs were obtained from 79 dietetic internship and 46 coordinated undergraduate program directors. Research courses were required in 60% of the programs and most often included basic statistics and review of the literature. Attendance at research conferences and observation of research dietitians were the most frequent learning experience activities. A wide variety of research projects were required by 71 % of the programs, but there were few student opportunities to participate in faculty-sponsored research. The ability to evaluate literature critically, knowledge of research concepts, and application of research findings to dietetic practice were the most frequently cited competency statements. Less than 2% of graduates in a 3-year period had published in professional journals. Faculty members believed they needed more time, money, educational materials, professional development, and access to research facilities to improve the research component of the program. These findings suggest that research competencies may need to be prioritized differently in view of changing needs in dietetic practice. J Am Diet Assoc 89:1676-1679, 1989.