[Energy expenditure in critically ill children: correlation with clinical characteristics, caloric intake, and predictive equations]. / Consumo calórico en el niño crítico: relación con las características clínicas, el aporte calórico y las fórmulas teóricas de cálculo de las necesidades.

ABSTRACT

OBJECTIVE: To study energy expenditure (EE) in critically ill infants and children and its correlation with clinical characteristics, treatment, nutrition, caloric intake, and predicted energy expenditure calculated through theoretical formulas. PATIENTS AND METHODS: A prospective observational study was conducted in critically ill infants and children. Indirect calorimetry measurements were performed using the calorimetry module of the S5 Datex monitor. Data on mechanical ventilation, nutrition, and caloric intake were registered. Theoretical equations of energy requirement (WHO/FAO, Harris-Benedict, Caldwell-Kennedy, Maffeis, Fleisch, Kleiber and Hunter) were calculated. The statistical analysis was performed using the SPSS 12.0 package. RESULTS: Sixty-eight EE determinations were performed in 43 critically ill infants and children aged between 10 days and 15 years old. Measured EE was 58.4 (18.4) kcal/kg/day, with wide individual variability. EE was significantly lower in infants and children who had undergone cardiac surgery than in the remainder. No correlation was found between EE and mechanical ventilation parameters, vasoactive drugs, sedatives, or muscle relaxants. A correlation was found between caloric intake and EE. In a high percentage of patients, predictive equations did not accurately estimate EE. The respiratory quotient was not useful to diagnose overfeeding or underfeeding. CONCLUSIONS: Wide individual variability in EE was found in critically ill infants and children. Predictive equations did not accurately estimate EE. Indirect calorimetry measured by a specific module is a simple method that could allow generalized use of EE measurement in critically ill pediatric patients undergoing mechanical ventilation.