title: Simultaneous mass spectrometry and thermoconductivity measurements of end-tidal xenon concentrations: a comparison.
abstract: Studies in which the rate of local cerebral blood flow is determined by xenon-enhanced computerized tomography require measurement of end-tidal gas. A mass spectrometer and a thermoconductivity detector were compared in measuring the concentration of xenon in end-tidal gas both in humans and in a clinically simulated ("breathing bag") system. The experiments showed that the two instruments provided virtually identical results up to a rate of 18 breaths/min, at which rate recorded concentrations showed marginal degradation with the thermoconductivity detector. Given the absence of a significant difference in the ability of the mass spectrometer and the thermoconductivity detector to measure end-tidal xenon concentration, the thermoconductivity detector appears to be a satisfactory alternative in studies measuring the rate of local cerebral blood flow by enhanced computerized tomography.
mesh_terms: D002560:Cerebrovascular Circulation; D006801:Humans; D013058:Mass Spectrometry; D013814:Thermal Conductivity; D013990:Tidal Volume; D014057:Tomography, X-Ray Computed; D014978:Xenon
chemical_list: D014978:Xenon