Biomaterial Database

Isovolume pressure-flow relationships in intrapulmonary bronchi of excised dog lungs. 1982

S Suzuki, and H Sasaki, and K Sekizawa, and T Takishima

From excised dog lungs we isolated airtight the intrapulmonary main bronchi (5-6 cm in length) with beads according to the technique described by Takishima et al. (J. Appl. Physiol. 38: 875-881, 1975), except for the most distal bronchus in which a retrograde catheter was inserted into the pleural surface of the lung. Air flowed from the retrograde catheter to the isolated main lobar bronchi at a given transpulmonary pressure (PL) with variable dynamic rates of driving pressure. We studied isovolume pressure-flow (IVPF) curves in the isolated intrapulmonary bronchi. The IVPF curves showed maximum expiratory flow (Vmax) and negative effort dependence. Vmax increased with increased PL and with increased dynamic rate of driving pressure and decreased with increased peripheral airway resistance added to the retrograde catheter. Bronchograms showed that dynamic compression occurred near the outlet of the isolated bronchi. When the isolated bronchi were dissected free from the surrounding parenchyma, Vmax decreased by 20-30% compared with Vmax in intact bronchi. We concluded that Vmax in intrapulmonary bronchi is preserved by mechanical interdependence between bronchi and parenchyma.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D012123	Pulmonary Ventilation	The total volume of gas inspired or expired per unit of time, usually measured in liters per minute.	Respiratory Airflow,Ventilation Tests,Ventilation, Pulmonary,Expiratory Airflow,Airflow, Expiratory,Airflow, Respiratory,Test, Ventilation,Tests, Ventilation,Ventilation Test
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
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia