@article{3091590,
    title = "Unevenness of ventilation assessed by the expired CO2 gas volume versus
V-T curve in asthmatic patients",
    author = "Koulouris, NG and Latsi, P and Stavrou, E and Chroneou, A and Gaga, M and and Jordanoglou, J",
    journal = "Respiratory Physiology & Neurobiology",
    year = "2004",
    volume = "140",
    number = "3",
    pages = "293-300",
    publisher = "Elsevier",
    issn = "1569-9048",
    doi = "10.1016/j.resp.2004.01.005",
    keywords = "disease; COPD; gas exchange; CO2 expirogram; heterogeneity; ventilation;
mammals; humans; ventilation; alveolar; uneven",
    abstract = "Recently, we have shown that the expired CO2 gas volume versus tidal
volume (V-CO2-V-T) curve is a useful tool for assessing unevenness of
ventilation because it allows the separation of tidal volume into three
functional compartments: (a) the CO2-free expired air (V-0), (b) the
transitional volume (V-tr), (c) the alveolar volume (V-A) and the
measurement of alveolar F-CO2 during resting breathing in normal
subjects and patients with COPD. In this paper, we have investigated
whether changes pertaining to unevenness of ventilation taking place
immediately after the administration of methacholine can be assessed
using the V-CO2-V-T curve in asthmatic patients.
The V-CO2-V-T curve was obtained during tidal breathing from 16 stable
asthmatic patients who underwent a methacholine challenge test. It has
been found that the V-tr, and hence Bohr’s dead space (V-D,V-Bohr = V-0
+ V-tr), over tidal volume ratios were significantly increased
immediately after the methacholine administration, whilst the V-0 over
tidal volume ratio was not affected. The change of the above ratios was
not related to the percentage decrease of FEV1.0 following methacholine
administration. (C) 2004 Elsevier B.V. All rights reserved."
}