title: Adaptive alterations in metabolism: practical consequences on energy requirements in the severely ill patient.
abstract: OBJECTIVE
  A recent and large multicentre study reports that ICU patients receive less than half of the recommended energy requirement. This review aims at clarifying whether underfeeding is scientifically justified or sustained by evidence-based medicine.
  
  
  RESULTS
  There is evidence that optimal nutrition improves clinical outcome of critically ill patients. The deleterious effect of overfeeding ICU patients is now well acknowledged, but underfeeding is not scientifically justified in ICU patients. Total energy expenditure in ICU patients is variable and methods to predict resting energy expenditure are questionable in these patients.
  
  
  CONCLUSIONS
  There is a need to measure energy expenditure in clinical practice. When not possible, the current guidelines on artificial nutrition (i.e. 25 kcal/kg per day) should be applied in order to limit underfeeding.
authors.affiliation: Bioénergétique Fondamentale et Appliquée, Université Joseph Fourier, Grenoble Cedex, France. eric.fontaine@ujf-grenoble.fr
authors.forename: Eric
authors.initials: E
authors.lastname: Fontaine
authors.forename: Manfred J
authors.initials: MJ
authors.lastname: Müller
mesh_terms: D001481:Basal Metabolism / Q000502:physiology*; D003422:Critical Care; D016638:Critical Illness / Q000628:therapy*; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D019317:Evidence-Based Medicine; D006801:Humans; D009751:Nutritional Requirements; D018529:Nutritional Support