Contribution of serial and parallel microperfusion to spatial variability in pulmonary inter- and intra-acinar blood flow
- 1 May 2010
- journal article
- research article
- Published by American Physiological Society in Journal of Applied Physiology
- Vol. 108 (5), 1116-1126
- https://doi.org/10.1152/japplphysiol.01177.2009
Abstract
This study presents a theoretical model of combined series and parallel perfusion in the human pulmonary acinus that maintains computational simplicity while capturing some important features of acinar structure. The model provides a transition between existing models of perfusion in the large pulmonary blood vessels and the pulmonary microcirculation. Arterioles and venules are represented as distinct elastic vessels that follow the branching structure of the acinar airways. These vessels are assumed to be joined at each generation by capillary sheets that cover the alveoli present at that generation, forming a “ladderlike” structure. Compared with a model structure in which capillary beds connect only the most distal blood vessels in the acinus, the model with combined serial and parallel perfusion provides greater capacity for increased blood flow in the lung via capillary recruitment when the blood pressure is elevated. Stratification of acinar perfusion emerges in the model, with red blood cell transit time significantly larger in the distal portion of the acinus compared with the proximal portion. This proximal-to-distal pattern of perfusion may act in concert with diffusional screening to optimize the potential for gas exchange.Keywords
This publication has 46 references indexed in Scilit:
- Anatomically based finite element models of the human pulmonary arterial and venous trees including supernumerary vesselsJournal of Applied Physiology, 2005
- Distensibility of the normal human lung circulation during exerciseAmerican Journal of Physiology-Lung Cellular and Molecular Physiology, 2005
- Pulmonary-Hepatic vascular Disorders (PHD)European Respiratory Journal, 2004
- Pulmonary transit time and diffusion limitation during heavy exercise in athletesRespiration Physiology, 1996
- Morphometry of the human pulmonary acinusThe Anatomical Record, 1988
- Finite element modeling of lungs including interlobar fissures and the heart cavityJournal of Biomechanics, 1983
- Direct Measurement of Microvascular Pressures in the Isolated Perfused Dog LungScience, 1980
- Mechanical Influences on the Pulmonary MicrocirculationAnnual Review of Physiology, 1980
- The normal human lung: ultrastructure and morphometric estimation of diffusion capacityRespiration Physiology, 1978
- Stratified Pulmonary Blood Flow: Some Consequences in Emphysema and Pulmonary EmbolismBMJ, 1969