Energy expenditure and substrate utilization in the newborn receiving total parenteral nutrition

Identifier:  PC:1738

Handle: https://hdl.handle.net/20.500.11797/PC1738

Authors:  J Salas Salvado; J Molina Gonzalez; J Figueras Aloy; J Masso Minuesa; C Martí-Henneberg; R Jimenez Gonzalez

Abstract:
A total of 26 newborns, subdivided into the groups, were studied during continuously administered total parenteral nutrition (TPN) to evaluate the effect on energy metabolism of three different isocaloric isonitrogenous solutions. These solutions varied only in the proportions of calories derived from fat and glucose. Nonprotein energy intake (88 Kcal/kg/d) was provided in a glucose/fat mixture with the proportion of fat being 18% (Group A; n=9), 29% (Group B; n=9) or 40% (Group C; n=8). Protein (2.15 g/kg/d) intake was maintained constant in all groups. Energy expenditure and substrate utilization were measured by indirect calorimetry during a 6 hr period. Energy expenditure was significantly lower and storage higher in group C relative to group B patients (p<0.05). Glucose oxidation increased with increasing total glucose intake (p<0.05). Net fat oxidation was observed in all groups and increased with the increasing percentage of energy infused as fat (p<0.05). Group A showed greater protein oxidation than group B (p<0.01) and C (p<0.05). In these groups, protein retention was more efficient. These data suggest that TPN regimens containing between 30 and 40% of the calories as fat emulsion reduces protein oxidation and enhances protein retention, suggesting that the 40% fat solutions may be more energy efficient.