Resting energy expenditure in children in a pediatric intensive care unit: comparison of Harris-Benedict and Talbot predictions with indirect calorimetry values

Abstract

The use of prediction equations has been recommended for calculating energy expenditure. We evaluated two equations that predict energy expenditure, each of which were corrected for two different stress factors, and compared the values obtained with those calculated by indirect calorimetry. The subjects were 55 critically ill children on mechanical ventilation. Basal metabolic rates were calculated with the Harris-Benedict and Talbot methods. Measured resting energy expenditure was 4.72 +/- 2.53 MJ/d. The average difference between measured resting energy expenditure and the Harris-Benedict prediction with a stress factor of 1.5 was -0.98 MJ/d, with an SD delta of 1.56 MJ/d and limits of agreement from -4.12 to 2.15; for a stress factor of 1.3 the average difference was -0.22 MJ/d, with an SD delta of 1.57 MJ/d and limits of agreement from -3.37 to 2.93. The average difference between measured resting energy expenditure and the Talbot prediction with a stress factor of 1.5 was -0.23 MJ/d, with an SD delta of 1.36 MJ/d and limits of agreement from -2.95 to 2.48; for a stress factor of 1.3, it was 0.42 MJ/d, with an SD delta of 1.24 MJ/d and limits of agreement from -2.04 to 2.92. These limits of agreement indicate large differences in energy expenditure between the measured value and the prediction estimated for some patients. Therefore, neither the Harris-Benedict nor the Talbot method will predict resting energy expenditure with acceptable precision for clinical use. Indirect calorimetry appears to be the only useful way of determining resting energy expenditure in these patients.

Variation in the application of methods used for predicting energy requirements in acutely ill adult patients: a survey of practice

“…This study aimed to determine current methods used by Australian dietitians for estimating energy requirements of patients and the variability of the outcomes of the calculations. Measurement of energy expenditure is the most accurate method for determining energy requirements (Jequier & Schutz, 1983;Soares et al, 1989;Coss-Bu et al, 1998;Flancbaum et al, 1999). These methods, however, are difficult in the clinical setting as they are expensive, have long measurement times, require trained personnel to perform them and are impractical (Mifflin et al, 1990;Flancbaum et al, 1999).…”

“…The success of nutrition support relies on the provision of adequate energy and nutrients, which in turn is based on dietitians accurately estimating energy requirements (Roza & Shizgal, 1984), while avoiding any negative outcomes associated with under-or overfeeding (Coss-Bu et al, 1998;White, 1998;Flancbaum et al, 1999;Gibney, 2000). Theoretically, to maintain weight within 71 kg over 3 months, energy intake should be within 73-6% of energy expenditure, based on energy requirements between 6000 and 12 000 kJ/day (1433-2867 kcal/day) (Reeves & Capra, 2003).…”

Is Indirect Calorimetry a Necessity or a Luxury in the Pediatric Intensive Care Unit?

“…1,2 Acute injury, inflammation, surgery, or sepsis markedly alters energy needs by inducing hyper-and hypometabolic conditions [3][4][5] that may be present in a single patient at different time points in the continuum of care. It is essential to provide the appropriate energy, substrate distribution, and micronutrients necessary to support the ongoing metabolic and stress response to avoid the loss of critical lean body mass and worsening of any existing nutrient deficiencies.…”

Factors That Influence the Agreement in Energy Expenditure Assessment in Pediatric Intensive Care Patients

“…8 The ability to assess energy expenditure can be difficult, especially in pediatric intensive care patients who require mechanical ventilatory support. 4,[9][10][11][12][13][14][15][16] In such settings, nutritionists use a combination of set equations often involving stress and growth factors to indirectly determine a patient's estimated energy expenditure (EEE).…”