Title :
Alveolar volume and sequential filling impact the estimation of D LCO and DLNO
Author :
Tsoukias, N.M. ; Dabdub, D. ; Wilson, A.F. ; George, S.C.
Author_Institution :
Dept. of Chem., California Univ., Irvine, CA, USA
Abstract :
This paper presents the development, testing, and application to experimental data of a new model to: (1) estimate the degree of sequential filling during inhalation, and (2) the dependence of the diffusing capacity (DL) on alveolar volume (VA). The model assesses sequential filling through a single parameter, k, where k=0 represents complete alveolar mixing, and k=1 represents no alveolar mixing (sequential filling). A linear (a+bVA) and an exponential (αVAβ) dependence of DL are used to describe the volume dependence of DL for carbon monoxide (CO) and nitric oxide (NO), respectively. Application of the model to experimental data from 7 normal humans predicts k=0.51 (0.35), b=0.69 (0.79), and β=0.65 (0.19) (mean(SD)). We conclude: (1) DL depends on lung volume (strongly for NO, weakly for CO), and (2) the effect of sequential filling must be considered when estimating DL
Keywords :
biodiffusion; lung; physiological models; pneumodynamics; sensitivity analysis; Jones-Meade method; alveolar mixing; alveolar volume; degree of sequential filling; diffusing capacity; exhalation; exponential dependence; gas exchange; inhalation; linear dependence; lung volume; model development; sensitivity analysis; Aerospace engineering; Chemical engineering; Data analysis; Filling; Humans; Lungs; Materials science and technology; Predictive models; Sequential analysis; Testing;
Conference_Titel :
[Engineering in Medicine and Biology, 1999. 21st Annual Conference and the 1999 Annual Fall Meetring of the Biomedical Engineering Society] BMES/EMBS Conference, 1999. Proceedings of the First Joint
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-5674-8
DOI :
10.1109/IEMBS.1999.802423
