title: Validity and reliability of a new portable telemetric calorimeter designed to measure oxygen consumption and carbon dioxide production.
abstract: OBJECTIVE
  The purpose of the present study was to evaluate the precision and the accuracy of a new portable telemetric calorimeter developed for the measurement of oxygen consumption, carbon dioxide production and pulmonary ventilation.
  
  
  METHODS
  An in vitro validation study.
  
  
  METHODS
  An experimental protocol was designed to generate a series of tidal volumes (from 100 ml to 6000 ml at 200 ml steps) at different respiratory rates (5, 8, 14, 20, 40, 60, 75 breaths-min(-1)). For this purpose, a standardized pulmonary waveform generator system was utilized. Moreover, in order to evaluate the measure of O2 and CO2 concentrations at different temperatures (-10 degrees, 0 degrees, 15 degrees, 25 degrees, 40 degrees C), the instrument was placed inside an adjustable temperature and humidity chamber.
  
  
  RESULTS
  The accuracy of flow measurements was within +/-3% in respect to the real values throughout the entire range of physiological values, whereas the measurements of gas concentrations were within +/-1% between 0 and 25 degrees C.
  
  
  CONCLUSIONS
  The new portable telemetric calorimeter represents an easy to use instrument for the measure of energy expenditure during the activities of daily living.
authors.affiliation: Human Nutrition Unit, Tor Vergata University, Rome, Italy. delorenzo@uniroma2.it
authors.forename: A
authors.initials: A
authors.lastname: De Lorenzo
authors.forename: R P
authors.initials: RP
authors.lastname: Sorge
authors.forename: I
authors.initials: I
authors.lastname: Bertini
authors.forename: A
authors.initials: A
authors.lastname: Andreoli
authors.forename: L
authors.initials: L
authors.lastname: lacopino
authors.forename: N
authors.initials: N
authors.lastname: Di Daniele
authors.forename: G
authors.initials: G
authors.lastname: Perriello
mesh_terms: D002153:Calorimetry, Indirect / Q000295:instrumentation* / Q000379:methods; D002245:Carbon Dioxide / Q000032:analysis* / Q000378:metabolism; D004734:Energy Metabolism; D004867:Equipment Design; D006801:Humans; D010100:Oxygen / Q000032:analysis* / Q000378:metabolism; D010101:Oxygen Consumption; D012016:Reference Values; D015203:Reproducibility of Results; D012119:Respiration; D012680:Sensitivity and Specificity; D013686:Telemetry / Q000295:instrumentation*
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen