Biomaterial Database

Lobar flow patterns in a hollow cast of canine central airways. 1983

B Snyder, and M J Jaeger

To demonstrate that the regional partitioning of flow in central airways is direction dependent, we compared inspiratory and expiratory lobar flows in a hollow rigid cast of canine lungs. Lobar flows were measured by a hot-wire anemometer, simultaneous tracheal flows by a pneumotachograph, and data displayed as (lobar) flow-(tracheal) flow curves. For tracheal airflows between 50 and 370 ml/s, we found that inspiratory apical flows were smaller, and basal flows larger, than corresponding expiratory distributions. This effect was largely extinguished by substituting a gas mixture of 85% He-15% N2; resulting regional flows were comparable to expiratory distributions obtained on room air. Thus canine central airways structure induces a kinematically irreversible flow pattern, consistent with a model of "cascade flow" in which branching structure modifies the distribution only of inspiratory flow. These results support Fowler's concept that lung regions fill and empty sequentially and may be pertinent to analyses of regional washout.

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
D008953	Models, Anatomic	Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.	Anatomic Models,Models, Surgical,Moulages,Models, Anatomical,Anatomic Model,Anatomical Model,Anatomical Models,Model, Anatomic,Model, Anatomical,Model, Surgical,Moulage,Surgical Model,Surgical Models
D008961	Models, Structural	A representation, generally small in scale, to show the structure, construction, or appearance of something. (From Random House Unabridged Dictionary, 2d ed)	Model, Structural,Structural Model,Structural Models
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
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