title: Indirect calorimetry in nutritional therapy. A position paper by the ICALIC study group.
abstract: This review aims to clarify the use of indirect calorimetry (IC) in nutritional therapy for critically ill and other patient populations. It features a comprehensive overview of the technical concepts, the practical application and current developments of IC.
  
  
  
  Pubmed-referenced publications were analyzed to generate an overview about the basic knowledge of IC, to describe advantages and disadvantages of the current technology, to clarify technical issues and provide pragmatic solutions for clinical practice and metabolic research. The International Multicentric Study Group for Indirect Calorimetry (ICALIC) has generated this position paper.
  
  
  
  IC can be performed in in- and out-patients, including those in the intensive care unit, to measure energy expenditure (EE). Optimal nutritional therapy, defined as energy prescription based on measured EE by IC has been associated with better clinical outcome. Equations based on simple anthropometric measurements to predict EE are inaccurate when applied to individual patients. An ongoing international academic initiative to develop a new indirect calorimeter aims at providing innovative and affordable technical solutions for many of the current limitations of IC.
  
  
  
  Indirect calorimetry is a tool of paramount importance, necessary to optimize the nutrition therapy of patients with various pathologies and conditions. Recent technical developments allow broader use of IC for in- and out-patients.
authors.affiliation: Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana Chuou-ku, Chiba City, Chiba 260-8677, Japan. Electronic address: t_oshima@chiba-u.jp.
authors.forename: Taku
authors.initials: T
authors.lastname: Oshima
authors.affiliation: Adult Intensive Care, Lausanne University Hospital, 1011 Lausanne, Switzerland. Electronic address: Mette.Berger@chuv.ch.
authors.forename: Mette M
authors.initials: MM
authors.lastname: Berger
authors.affiliation: Department of Intensive Care, Vrije Universiteit Brussel, Brussels, Belgium. Electronic address: Elisabeth.DeWaele@uzbrussel.be.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: De Waele
authors.affiliation: Department of Anaesthesiology and Intensive Care, Haukeland University Hospital, Jonas Liesvei 65, 5021 Bergen, Norway; Department of Clinical Medicine University of Bergen, Bergen, Norway; Haukeland Universitetssykehus Laboratoriebygget, 7. etg. Heis øst, Norway. Electronic address: anne.guttormsen@helse-bergen.no.
authors.forename: Anne Berit
authors.initials: AB
authors.lastname: Guttormsen
authors.affiliation: Service of Intensive Care, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland. Electronic address: claudia-paula.heidegger@hcuge.ch.
authors.forename: Claudia-Paula
authors.initials: CP
authors.lastname: Heidegger
authors.affiliation: Division of Cardiac Thoracic Vascular Anesthesia and Intensive Care Medicine, University Hospital of Vienna, Waehrihger Guertel 18-20, 1090 Vienna, Austria. Electronic address: michael.hiesmayr@meduniwien.ac.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Hiesmayr
authors.affiliation: Critical Care Medicine, Institute for Nutrition Research, Rabin Medical Center, Beilison Hospital, Petah Tikva 49100, Israel. Electronic address: psinger@clalit.org.il.
authors.forename: Pierre
authors.initials: P
authors.lastname: Singer
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Karolinska University Hospital Huddinge, Sweden. Electronic address: jan.wernerman@karolinska.se.
authors.forename: Jan
authors.initials: J
authors.lastname: Wernerman
authors.affiliation: Nutrition Unit, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland. Electronic address: claude.pichard@unige.ch.
authors.forename: Claude
authors.initials: C
authors.lastname: Pichard
mesh_terms: D002153:Calorimetry, Indirect; D016638:Critical Illness / Q000628:therapy*; D016208:Databases, Factual; D004734:Energy Metabolism; D006801:Humans; D007297:Inpatients; D007362:Intensive Care Units; D009751:Nutritional Requirements; D018529:Nutritional Support; D010045:Outpatients; D012146:Rest
keywords: Carbon dioxide production (VCO(2)); Energy expenditure (EE); Indirect calorimetry; Oxygen consumption (VO(2)); Respiratory quotient (RQ); Resting energy expenditure (REE)