Journal of Applied Physiology, Vol 73, Issue 3 862-873, Copyright © 1992 by American Physiological Society

ARTICLES

Aerosol bolus dispersion and convective mixing in human and dog lungs and physical models

F. S. Rosenthal, J. D. Blanchard and P. J. Anderson
School of Health Sciences, Purdue University, West Lafayette, Indiana 47907.

The dispersion of aerosol boluses in the lung is a probe for convective mixing and has been proposed as a marker for abnormal lung function. To better understand the factors underlying this phenomenon, aerosol dispersion was compared in human subjects, dogs, and various physical models. In all systems, dispersion increased with the volumetric penetration of the aerosol bolus. The rate of this increase was 83% greater in humans compared with dogs. Dispersion in dogs was close to that in a packed bed with beads of 2.5 mm. Aerosol dispersion decreased with increasing flow rate in human subjects. An artificial larynx inserted into the straight tube caused a 33% increase in dispersion. In humans, aerosol dispersion was significantly correlated with forced expired flow between 25 and 75% of vital capacity. A 2-s pause between inspiration and expiration increased dispersion 23-58% in three isolated dog lungs but did not affect dispersion in the packed bed. The data suggest that lung geometry, flow rate, particle mobility, and the larynx all significantly affect aerosol dispersion by influencing the reversibility of aerosol transport between inspiration and expiration.

This article has been cited by other articles:

				F. S. Henry, J. P. Butler, and A. Tsuda Kinematically irreversible acinar flow: a departure from classical dispersive aerosol transport theories J Appl Physiol, February 1, 2002; 92(2): 835 - 845. [Abstract] [Full Text] [PDF]

				S. Verbanck, D. Schuermans, W. Vincken, and M. Paiva Saline aerosol bolus dispersion. I. The effect of acinar airway alteration J Appl Physiol, May 1, 2001; 90(5): 1754 - 1762. [Abstract] [Full Text] [PDF]

				S. Verbanck, D. Schuermans, M. Paiva, and W. Vincken Saline aerosol bolus dispersion. II. The effect of conductive airway alteration J Appl Physiol, May 1, 2001; 90(5): 1763 - 1769. [Abstract] [Full Text] [PDF]

				C. Darquenne, M. Paiva, and G. K. Prisk Effect of gravity on aerosol dispersion and deposition in the human lung after periods of breath holding J Appl Physiol, November 1, 2000; 89(5): 1787 - 1792. [Abstract] [Full Text] [PDF]

				C. Darquenne, J. B. West, and G. K. Prisk Dispersion of 0.5- to 2-µm aerosol in µG and hypergravity as a probe of convective inhomogeneity in the lung J Appl Physiol, April 1, 1999; 86(4): 1402 - 1409. [Abstract] [Full Text] [PDF]

				F. S. Rosenthal Aerosol probes of lung injury in a 28-wk longitudinal study of mild experimental emphysema in dogs J Appl Physiol, February 1, 1999; 86(2): 725 - 731. [Abstract] [Full Text] [PDF]

				J. S. Brown, T. R. Gerrity, and W. D. Bennett Effect of ventilation distribution on aerosol bolus dispersion and recovery J Appl Physiol, December 1, 1998; 85(6): 2112 - 2117. [Abstract] [Full Text] [PDF]

				C. Darquenne, J. B. West, and G. K. Prisk Deposition and dispersion of 1-µm aerosol boluses in the human lung: effect of micro- and hypergravity J Appl Physiol, October 1, 1998; 85(4): 1252 - 1259. [Abstract] [Full Text] [PDF]