Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 85: 333-352, 1998;
8750-7587/98 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Halpern, D.
Right arrow Articles by Grotberg, J. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Halpern, D.
Right arrow Articles by Grotberg, J. B.
Vol. 85, Issue 1, 333-352, July 1998

MODELING IN PHYSIOLOGY
A theoretical study of surfactant and liquid delivery into the lung

D. Halpern1, O. E. Jensen2, and J. B. Grotberg3

1 Department of Mathematics, University of Alabama, Tuscaloosa, Alabama 35487; 2 Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 9EW, United Kingdom; and 3 Department of Biomedical Engineering, Northwestern University, Evanston, 60208, and Department of Anesthesiology, Northwestern University Medical School, Chicago, Illinois 60611

A computational study is presented for the transport of liquids and insoluble surfactant through the lung airways, delivered from a source at the distal end of the trachea. Four distinct transport regimes are considered: 1) the instilled bolus may create a liquid plug that occludes the large airways but is forced peripherally during mechanical ventilation; 2) the bolus creates a deposited film on the airway walls, either from the liquid plug transport or from direct coating, that drains under the influence of gravity through the first few airway generations; 3) in smaller airways, surfactant species form a surface layer that spreads due to surface-tension gradients, i.e., Marangoni flows; and 4) the surfactant finally reaches the alveolar compartment where it is cleared according to first-order kinetics. The time required for a quasi-steady-state transport process to evolve and for the subsequent delivery of the dose is predicted. Following fairly rapid transients, on the order of seconds, steady-state transport develops and is governed by the interaction of Marangoni flow and alveolar kinetics. Total delivery time is ~24 h for a typical first dose. Numerical solutions show that both transit and delivery times are strongly influenced by the strength of the preexisting surfactant and the geometric properties of the airway network. Delivery times for follow-up doses can increase significantly as the level of preexisting surfactant rises.

pulmonary surfactant; drug delivery; surfactant replacement therapy; respiratory distress syndrome; Marangoni flow; airway liquid; surface tension dynamics; pulmonary fluid mechanics


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
J. C. Anderson, R. C. Molthen, C. A. Dawson, S. T. Haworth, J. L. Bull, M. R. Glucksberg, and J. B. Grotberg
Effect of ventilation rate on instilled surfactant distribution in the pulmonary airways of rats
J Appl Physiol, July 1, 2004; 97(1): 45 - 56.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
J. L. Bull, S. Tredici, E. Komori, D. O. Brant, J. B. Grotberg, and R. B. Hirschl
Distribution dynamics of perfluorocarbon delivery to the lungs: an intact rabbit model
J Appl Physiol, May 1, 2004; 96(5): 1633 - 1642.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
K. J. Cassidy, J. L. Bull, M. R. Glucksberg, C. A. Dawson, S. T. Haworth, R. Hirschl, N. Gavriely, and J. B. Grotberg
A rat lung model of instilled liquid transport in the pulmonary airways
J Appl Physiol, May 1, 2001; 90(5): 1955 - 1967.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
R. T. SCHERMULY, A. GÜNTHER, N. WEISSMANN, H. A. GHOFRANI, W. SEEGER, F. GRIMMINGER, and D. WALMRATH
Differential Impact of Ultrasonically Nebulized Versus Tracheal-instilled Surfactant on Ventilation-Perfusion (VA/Q) Mismatch in a Model of Acute Lung Injury
Am. J. Respir. Crit. Care Med., January 1, 2000; 161(1): 152 - 159.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online