Acinar and conductive ventilation heterogeneity in severe CF lung disease: back to the model.

Research output: Contribution to journalArticle

33 Citations (Scopus)


Severe convective ventilation heterogeneity occurring in CF lung disease requires a modified method to determine acinar and conductive components of ventilation heterogeneity from normalized phase III slope (Sn) curves. Modified Sacin* and Scond* (as opposed to standard Sacin and Scond) are proposed and interpreted on the basis of 2 conceptual mechanisms: (a) flow asynchrony between two convection-dependent units with a different specific ventilation, but with an identical acinus inside each unit (generating an identical diffusion-convection-dependent portion of Sn); (b) different specific ventilation (without any flow asynchrony) between two convection-dependent units with the worst ventilated unit containing an abnormal acinus generating the greatest diffusion-convection-dependent portion of Sn. In CF patients with an abnormal lung clearance index (LCI), Scond* (but not Scond) and Sacin* were significant contributors to LCI (beta(Scond*)=0.70; beta(Sacin*)=0.49; P <0.001 for both). Mechanism (a) can entirely account for experimental Scond* values, while mechanism (b) implies that experimental Sacin* values are likely dominated by peripheral ventilation heterogeneity in the best ventilated portions of the lung.
Original languageEnglish
Pages (from-to)124-132
Number of pages9
JournalRespir Physiol Neurobiol
Issue number2
Publication statusPublished - Aug 2013


  • Inert-gas washout
  • cystic-fibrosis
  • clearance index
  • airways
  • maldistribution
  • utility
  • slope
  • lung disease

Fingerprint Dive into the research topics of 'Acinar and conductive ventilation heterogeneity in severe CF lung disease: back to the model.'. Together they form a unique fingerprint.

Cite this