Biomaterial Database

Analysis of bronchial mechanics and density dependence of maximal expiratory flow. 1986

R K Lambert

The computational model for expiratory flow in humans of Lambert and associates (J. Appl. Physiol. Respirat. Environ. Exercise Physiol. 52: 44-56, 1982) was used to investigate the effect of bronchial constrictions in three airway zones on the density dependence of maximal expiratory flow. It was found that constriction of the peripheral airways (less than 2 mm diam) reduced density dependence and increased the volume of isoflow. Constriction of the larger intraparenchymal airways resulted in increased density dependence at low lung volumes and essentially normal values at other volumes. The volume of isoflow was reduced. Extraparenchymal (but intrathoracic) airway constriction caused no change in the volume of isoflow but caused increased density dependence at the higher lung volumes. It was shown that in these model simulations the addition of extraparenchymal constriction to intraparenchymal constriction causes essentially no changes in density dependence. An increased volume of isoflow and significantly decreased density dependence at 50 and 25% vital capacity were produced by simulated constrictions only in the peripheral airways.

UI	MeSH Term	Description	Entries
D008448	Maximal Expiratory Flow Rate	The airflow rate measured during the first liter expired after the first 200 ml have been exhausted during a FORCED VITAL CAPACITY determination. Common abbreviations are MEFR, FEF 200-1200, and FEF 0.2-1.2.	Forced Expiratory Flow 0.2-1.2,Forced Expiratory Flow 200-1200,Flow Rate, Maximal Expiratory,MEFR,Forced Expiratory Flow 0.2 1.2,Forced Expiratory Flow 200 1200
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D001980	Bronchi	The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.	Primary Bronchi,Primary Bronchus,Secondary Bronchi,Secondary Bronchus,Tertiary Bronchi,Tertiary Bronchus,Bronchi, Primary,Bronchi, Secondary,Bronchi, Tertiary,Bronchus,Bronchus, Primary,Bronchus, Secondary,Bronchus, Tertiary
D005540	Forced Expiratory Flow Rates	The rate of airflow measured during a FORCED VITAL CAPACITY determination.	Expiratory Forced Flow Rates,Flow Rates, Expiratory Forced,Flow Rates, Forced Expiratory
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001696	Biomechanical Phenomena	The properties, processes, and behavior of biological systems under the action of mechanical forces.	Biomechanics,Kinematics,Biomechanic Phenomena,Mechanobiological Phenomena,Biomechanic,Biomechanic Phenomenas,Phenomena, Biomechanic,Phenomena, Biomechanical,Phenomena, Mechanobiological,Phenomenas, Biomechanic