help button home button
AJRCCM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
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
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by WAGNER, E. M.
Right arrow Articles by LIU, M. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by WAGNER, E. M.
Right arrow Articles by LIU, M. C.

Am. J. Respir. Crit. Care Med., Volume 157, Number 2, February 1998, 447-452

Direct Assessment of Small Airways Reactivity in Human Subjects

ELIZABETH M. WAGNER, EUGENE R. BLEECKER, SOLBERT PERMUTT, and MARK C. LIU

Department of Medicine, The Johns Hopkins Asthma and Allergy Center, Baltimore, Maryland

Our knowledge of airways reactivity to inflammatory agonists is derived predominantly from tests dominated by large airway responsiveness. To determine directly, the histamine responsiveness of the smallest airways, eight normal and 11 asymptomatic asthmatic subjects were studied utilizing a wedged bronchoscope technique. A fiberoptic bronchoscope was wedged in the anterior segment of the right upper lobe and a double-lumen catheter was advanced through the working channel to its tip. With a constant flow of gas (5% CO2 in air) through one lumen of the catheter, pressure at the tip of the bronchoscope was measured with the subject breath-holding at FRC. Peripheral airways resistance (Rp) was measured at baseline and after saline, histamine (10, 50, 100 mg/ml) and isoproterenol (2 mg/ml) challenge through the bronchoscope. Baseline Rp of asthmatics (0.041 ± 0.015 cm H2O/ml/min; mean ± SE) was significantly greater than normal subjects (0.011 ± 0.003 cm H2O/ml/ min; p = 0.019). The log of the concentration of histamine that caused a 100% increase in peripheral airways response was greater in the normal subjects than in the asthmatic subjects (p = 0.0114) and correlated with whole lung responsiveness to histamine in asthmatics (r = 0.847, p < 0.05). Isoproterenol reversed completely the increase in Rp in normal subjects but not asthmatic subjects. The results of this study demonstrate that the resistance of the smallest peripheral airways, when measured directly, increased when challenged locally with histamine in both normal subjects and asthmatic subjects. However, the peripheral airways responsiveness was significantly enhanced in asthmatic subjects relative to normal controls.




This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
D. A. Kaminsky, C. G. Irvin, L. Lundblad, H. T. Moriya, S. Lang, J. Allen, T. Viola, M. Lynn, and J. H. T. Bates
Oscillation mechanics of the human lung periphery in asthma
J Appl Physiol, November 1, 2004; 97(5): 1849 - 1858.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
M. KRAFT, J. PAK, R. J. MARTIN, D. KAMINSKY, and C. G. IRVIN
Distal Lung Dysfunction at Night in Nocturnal Asthma
Am. J. Respir. Crit. Care Med., June 1, 2001; 163(7): 1551 - 1556.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
A. WOHLSEN, S. UHLIG, and C. MARTIN
Immediate Allergic Response in Small Airways
Am. J. Respir. Crit. Care Med., May 1, 2001; 163(6): 1462 - 1469.
[Abstract] [Full Text]

Home page
 Am. J. Respir. Crit. Care Med.Home page
D. A. KAMINSKY and M. LYNN
Pulmonary Capillary Blood Volume in Hyperpnea-induced Bronchospasm
Am. J. Respir. Crit. Care Med., November 1, 2000; 162(5): 1668 - 1673.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Proc. Am. Thorac. Soc. Am. J. Respir. Cell Mol. Biol.
Copyright © 1998 American Thoracic Society 		  Tobacco