BJA Advance Access originally published online on August 21, 2006
British Journal of Anaesthesia 2006 97(5):718-731; doi:10.1093/bja/ael216
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
A tidally breathing model of ventilation, perfusion and volume in normal and diseased lungs
1 Department of Anaesthetics, The University of Sydney, Royal Prince Alfred Hospital Missenden Road, Camperdown, NSW 2050, Australia
2 Department of Respiratory Medicine, The University of Sydney, Royal Prince Alfred Hospital Missenden Road, Camperdown, NSW 2050, Australia
3 Department of Respiratory Medicine, Westmead Hospital Westmead, NSW 2145, Australia
*Corresponding author: Department of Anaesthetics, University of Sydney, Royal Prince Alfred Hospital, Building 89 Level 4, Missenden Road, Camperdown, NSW 2050, Australia. E-mail: mjturner{at}usyd.edu.au
Background. To simulate the short-term dynamics of soluble gas exchange (e.g. CO2 rebreathing), model structure, ventilationperfusion (
) and ventilationvolume (
) parameters must be selected correctly. Some diseases affect mainly the
distribution while others affect both
and
distributions. Results from the multiple inert gas elimination technique (MIGET) and multiple breath nitrogen washout (MBNW) can be used to select
and
parameters, but no method exists for combining
and
parameters in a multicompartment lung model.
Methods. We define a tidally breathing lung model containing shunt and up to eight alveolar compartments. Quantitative and qualitative understanding of the diseases is used to reduce the number of model compartments to achieve a unique solution. The reduced model is fitted simultaneously to inert gas retentions calculated from published
distributions and normalized MBNWs obtained from similar subjects. Normal lungs and representative cases of emphysema and embolism are studied.
Results. The normal, emphysematous and embolism models simplify to one, three and two alveolar compartments, respectively.
Conclusions. The models reproduce their respective MIGET and MBNW patient results well, and predict disease-specific steady-state and dynamic soluble and insoluble gas responses.
This article is accompanied by the Editorial.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
H. J. G. and R. J. J. Modelling: a core technique in anaesthesia and critical care research. Br. J. Anaesth., November 1, 2006; 97(5): 589 - 592. [Full Text] [PDF] |
||||
