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Transcutaneous Microcirculatory Imaging in Preterm Neonates
Published on: December 31, 2015
Determinants of energy expenditure in ventilated preterm infants
M P DeMarie1, A Hoffenberg, S L Biggerstaff
1Department of Pediatrics, University of Colorado Health Sciences Center, Denver, USA.
Insights
Energy expenditure (EE) in preterm infants increases with postnatal age and nutrient intake. Nonprotein calorie intake and postnatal age best predict EE, showing a significant interaction in ventilated infants during the first three weeks of life.
Area of Science:
- Neonatology
- Pediatric Critical Care
- Metabolic Research
Background:
- Preterm infants require careful monitoring of metabolic status.
- Understanding energy expenditure (EE) is crucial for optimizing growth and development in vulnerable neonates.
Purpose of the Study:
- To determine oxygen consumption (VO2), carbon dioxide production (VCO2), and EE in ventilated preterm infants.
- To identify key factors influencing EE during the first three weeks of life.
Main Methods:
- Indirect calorimetry was used to measure VO2, VCO2, and EE.
- Regression analysis assessed relationships between EE and demographic factors, nutrient intake, and illness severity.
- Repeated measures analysis accounted for multiple studies per infant.
Main Results:
- EE tended to increase over the first three weeks of life, with significant individual variability.
- Nonprotein calorie intake and postnatal age were the strongest predictors of EE.
- No correlation was found between EE and birthweight, current weight, gestational age, protein intake, or illness severity.
- A significant interaction between postnatal age and energy intake (EI) on EE was observed.
Conclusions:
- Energy expenditure in ventilated preterm infants is best predicted by postnatal age and energy intake.
- The interaction suggests that daily increases in substrate provision influence EE in this population.
Abstract:
The purpose of this study was to determine oxygen consumption (VO2), carbon dioxide production (VCO2), and energy expenditure (EE) in a group of preterm ventilated infants during the first 3 weeks of life, and to determine the major factors that influence EE. Thirty-eight indirect calorimetry studies were performed in 18 ventilated infants with mean gestational age of 27.9 +/- 0.6 (SEM) weeks. The relationship of demographic factors, nutrient intake, and severity of illness assessments of EE were determined by regression analysis. Repeated measure analysis was performed for the effect of multiple studies in the same patient. Although VO2, VCO2, and EE all tended to increase over the first 3 weeks of life, there was a wide range of values. EE was best predicted by nonprotein calorie intake and postnatal age, while there was no correlation with birthweight, weight at the time of study, gestational age, protein intake, or severity of illness. Multiple regression analyses demonstrated a strong interaction between PNA and EI. In this population EE is best predicted by PNA and EI. The interactive effect between PNA and EI on EE is probably explained by the clinical practice of daily increments in substrate intake in these patients.
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