title: Resting energy expenditure, macronutrient utilization, and body composition in term infants after corrective surgery of major congenital anomalies: A case-study.
abstract: BACKGROUND
  Knowledge on the metabolic changes and nutritional needs during the postsurgical anabolic phase in infants is scarce. This analysis explores the associations of resting energy expenditure (REE) and macronutrient utilization with body composition of full-term infants, during catch-up growth after corrective surgery of major congenital anomalies.
  
  
  METHODS
  A cohort of full-term appropriate for-gestational-age neonates subjected to corrective surgery of major congenital anomalies were recruited after gaining weight for at least one week. REE and macronutrient utilization, measured by respiratory quotient (RQ), were assessed by indirect calorimetry using the Deltatrac II Metabolic Monitor ®. Body composition, expressed as fat-free mass (FFM), fat mass (FM) and adiposity defined as percentage of FM (% FM), was measured by air displacement plethysmography using the Pea Pod ®.
  
  
  RESULTS
  Four infants were included at 3 to 5 postnatal weeks. Recommended energy and macronutrient intakes for healthy term infants were provided. Through the study, the median (min-max) REE (Kcal/Kg FFM/d) was 70.8 (60.6-96.1) and RQ was 0.99 (0.72-1.20). Steady increases in both body weight and FFM were associated with initial decrease in FM and adiposity followed by their increase. Low RQ preceded decrease in adiposity.
  
  
  CONCLUSIONS
  The marked adiposity depletion, not expected during steady weight gain in the postsurgical period, prompts us to report this finding. The subsequent adiposity catch-up was associated with relatively high REE and RQ, suggesting preferential oxidation of carbohydrates and preservation of lipids for fat storage.
authors.affiliation: Neonatal Intensive Care Unit, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.|Nutrition Lab, Department of Pediatrics, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.|Dietetics and Nutrition, Lisbon School of Health Technology, Lisbon, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Pereira-da-Silva
authors.affiliation: Nutrition Lab, Department of Pediatrics, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Rodrigues
authors.affiliation: Dietetics and Nutrition, Lisbon School of Health Technology, Lisbon, Portugal.
authors.forename: A C
authors.initials: AC
authors.lastname: Moreira
authors.affiliation: Research Unit, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.
authors.forename: D
authors.initials: D
authors.lastname: Virella
authors.affiliation: Research Unit, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Alves
authors.affiliation: Nutrition Lab, Department of Pediatrics, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Correia
authors.affiliation: Nutrition Lab, Department of Pediatrics, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal.
authors.forename: G
authors.initials: G
authors.lastname: Cordeiro-Ferreira
mesh_terms: D050154:Adiposity; D002153:Calorimetry, Indirect; D000013:Congenital Abnormalities / Q000601:surgery*; D004040:Dietary Carbohydrates / Q000378:metabolism; D004041:Dietary Fats / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011184:Postoperative Period; D015430:Weight Gain
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins
keywords: Adiposity; body composition; neonatal surgery; respiratory quotient; rest energy expenditure