title: Reliability and validity of non-invasive determined haemoglobin mass and blood volumes.
abstract: BACKGROUND
  The carbon monoxide (CO) rebreathing method used for the determination of haemoglobin mass (Hbmass) is associated with blood sample analysis (in this study: Radiometer ABL800). As an alternative hereto the aim of the present study was to evaluate the use of a portable and non-invasive CO pulse oximeter (Rad-57).
  
  
  METHODS
  With simultaneous determination of CO in the circulation by ABL800 (%HbCO) and Rad-57 (SpCO), Hbmassand blood volume (BV) were determined in duplicates in 24 volunteers. Percentage of typical errors (%TE) within methods and linear correlations between the two procedures were computed.
  
  
  RESULTS
  Hbmass(Rad-57 = 798 ± 230 g; ABL800 = 781 ± 192 g) and BV (Rad-57 = 5700 ± 1373 ml; ABL800 = 5581 ± 1096 ml) were similar between methods. However, the %TE for Hbmasswas higher (P<0·001) for Rad-57 (5·84 ± 5·29%) than for ABL800 (1·35 ± 1·13%). Similarly, the %TE for BV was higher (P<0·001) for Rad-57 (6·06 ± 5·76%) than for ABL800 (1·48 ± 1·25%). Lower (P<0·05) correlation coefficients between the methods were found when Hbmass> 905 g and BV > 6193 ml.
  
  
  CONCLUSIONS
  Assessment of SpCO by Rad-57 resulted in considerably less precise determinations of Hbmassand BV, especially for high values. Thus, non-invasive assessment of Hbmassand BV cannot be recommended for scientific purposes, but may nonetheless be useful in clinical settings.
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.|Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Nazzareno
authors.initials: N
authors.lastname: Fagoni
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.|Department of Nutrition, Exercise and Sports (NEXS), University of Copenhagen, Copenhagen, Denmark.
authors.forename: Andreas
authors.initials: A
authors.lastname: Breenfeldt Andersen
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.
authors.forename: Laura
authors.initials: L
authors.lastname: Oberholzer
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Haider
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.
authors.forename: Anne-Kristine
authors.initials: AK
authors.lastname: Meinild Lundby
authors.affiliation: Zurich Center of Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.
authors.forename: Carsten
authors.initials: C
authors.lastname: Lundby
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D015415:Biomarkers / Q000097:blood; D001810:Blood Volume; D001811:Blood Volume Determination / Q000295:instrumentation*; D002248:Carbon Monoxide / Q000008:administration & dosage / Q000097:blood*; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D016014:Linear Models; D008297:Male; D010092:Oximetry / Q000295:instrumentation*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D002248:Carbon Monoxide
keywords: CO pulse oximeter; CO rebreathing; blood gas analysis; carboxyhemoglobin; transcutaneous blood gas monitoring