title: Red cell volume determination using a stable isotope of chromium.
abstract: OBJECTIVE
  To validate and improve a method of red cell volume determination by use of a stable isotope of chromium.
  
  
  METHODS
  Twelve subjects were sequentially injected with red blood cells labeled with a stable isotope of chromium (53Cr) and red blood cells labeled with radioisotopic chromium (51Cr). Measurement of 53Cr dilution was by gas chromatography/mass spectrometry. Measurement of 51Cr dilution was by gamma counter.
  
  
  RESULTS
  Comparison of the two methods led to results that differed on average by 34.5 +/- 45.0 mL (1.8 +/- 2.2%), 0.3 to 3.2%, 95% confidence interval.
  
  
  CONCLUSIONS
  Measurement of red cell volume by use of a stable isotope of chromium is accurate, with potential applications including measurement in pregnant women and children or other groups in whom exposure to radioisotopes is undesirable.
authors.affiliation: Department of Obstetrics and Gynecology, Brown University, Women and Infants' Hospital of Rhode Island, Providence 02905, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Silver
authors.forename: M A
authors.initials: MA
authors.lastname: Seebeck
authors.forename: R M
authors.initials: RM
authors.lastname: Cowett
authors.forename: K Y
authors.initials: KY
authors.lastname: Patterson
authors.forename: C
authors.initials: C
authors.lastname: Veillon
mesh_terms: D001810:Blood Volume; D002859:Chromium Isotopes; D002860:Chromium Radioisotopes; D004911:Erythrocyte Volume; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D016014:Linear Models; D008297:Male
chemical_list: D002859:Chromium Isotopes; D002860:Chromium Radioisotopes