Journal of Applied Physiology, Vol 69, Issue 5 1670-1675, Copyright © 1990 by American Physiological Society

ARTICLES

Cough-enhanced mucus clearance in the normal lung

W. D. Bennett, W. M. Foster and W. F. Chapman
Department of Medicine, State University of New York, Stony Brook 11794.

We studied the effectiveness of cough for clearing mucus in 12 nonsmoking subjects with normal lung function. On 2 separate study days, each subject breathed 6-microns Mass Median Aerodynamic Diameter 99mTc-labeled iron oxide particles under controlled breathing conditions while they were seated in front of a gamma camera. Retention (R) of lung activity was measured over the initial 2 h and again at 24 h after particle inhalation. On the control day the subject sat quietly in front of the camera, while on the cough day each subject performed 60 controlled coughs during the 1st h of retention measurements. By paired analysis, retentions at both 1 and 2 h (R1 and R2, respectively) for the cough measurements were significantly less than control (mean control R1 = 85% vs. mean cough R1 = 72%, P less than 0.002; mean control R2 = 75% vs. mean cough R2 = 65%, P less than 0.02). Retention at 24 h (R24) was not significantly different between cough and control measurements (mean cough R24 = 35% and mean control R24 = 32%). Thus coughing increased the rate at which the radiolabeled particles were cleared from the bronchial airways in these individuals. Follow-up experiments with subjects performing rapid inhalations rather than cough showed similar enhanced particle clearance to that seen with cough. These results suggest that the observed enhancement of mucus clearance by cough (and rapid inhalation) in the normal lung may be due to a stimulation of the mucociliary apparatus rather than via a two-phase gas-liquid flow mechanism.

This article has been cited by other articles:

				P. Phelps, O. S. Cakmakkaya, C. C. Apfel, and O. C. Radke A Simple Clinical Maneuver to Reduce Laparoscopy-Induced Shoulder Pain: A Randomized Controlled Trial Obstet. Gynecol., May 1, 2008; 111(5): 1155 - 1160. [Abstract] [Full Text] [PDF]

				F. D. McCool Global Physiology and Pathophysiology of Cough: ACCP Evidence-Based Clinical Practice Guidelines Chest, January 1, 2006; 129(1_suppl): 48S - 53S. [Abstract] [Full Text] [PDF]

				R. Tarran, B. Button, M. Picher, A. M. Paradiso, C. M. Ribeiro, E. R. Lazarowski, L. Zhang, P. L. Collins, R. J. Pickles, J. J. Fredberg, et al. Normal and Cystic Fibrosis Airway Surface Liquid Homeostasis: THE EFFECTS OF PHASIC SHEAR STRESS AND VIRAL INFECTIONS J. Biol. Chem., October 21, 2005; 280(42): 35751 - 35759. [Abstract] [Full Text] [PDF]

				B. Hanel, I. Law, and J. Mortensen Maximal rowing has an acute effect on the blood-gas barrier in elite athletes J Appl Physiol, September 1, 2003; 95(3): 1076 - 1082. [Abstract] [Full Text] [PDF]

				N. Sood, W. D. Bennett, K. Zeman, J. Brown, C. Foy, R. C. Boucher, and M. R. Knowles Increasing Concentration of Inhaled Saline with or without Amiloride: Effect on Mucociliary Clearance in Normal Subjects Am. J. Respir. Crit. Care Med., January 15, 2003; 167(2): 158 - 163. [Abstract] [Full Text] [PDF]

				N. E. ALEXIS, S.-C. HU, K. ZEMAN, T. ALTER, and W. D. BENNETT Induced Sputum Derives from the Central Airways . Confirmation Using a Radiolabeled Aerosol Bolus Delivery Technique Am. J. Respir. Crit. Care Med., November 15, 2001; 164(10): 1964 - 1970. [Abstract] [Full Text] [PDF]