Biomaterial Database

Effect of resistive loading on inspiratory work output in anesthetized cats. 1984

L Zocchi, and S C Luijendijk, and W A Zin, and A Rossi, and J Milic-Emili

In five spontaneously breathing anesthetized cats, we determined the inspiratory elastic (Wel), resistive (Wres), and total (WI) mechanical work rates (power) during control and first loaded inspirations through graded linear resistances (delta R) by "Campbell diagrams" based on measurement of esophageal pressure. WI did not change with delta R's up to 0.31 cmH2O X ml-1 X s, the concomitant decrease in Wel being balanced by an increase in Wres. The stability of WI in the face of delta R's was due to the vagally mediated prolongation of inspiration and the intrinsic properties of the respiratory system and of the contracting inspiratory muscles. To assess the separate contributions of volume-related and flow-related intrinsic mechanisms to the stability of WI, we made model predictions of the immediate effects of delta R's on inspiratory mechanical work output based on measurements of inspiratory driving pressure waves and passive and active respiratory resistance and elastance on the same five cats. The results suggest that the intrinsic stability of WI in the face of delta R's is provided primarily by the active elastance.

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
D008170	Lung Compliance	The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)	Compliance, Lung,Compliances, Lung,Lung Compliances
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
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
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D000403	Airway Resistance	Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.	Airway Resistances,Resistance, Airway,Resistances, Airway
D000768	Anesthesia, General	Procedure in which patients are induced into an unconscious state through use of various medications so that they do not feel pain during surgery.	Anesthesias, General,General Anesthesia,General Anesthesias
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
D013314	Stress, Mechanical	A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.	Mechanical Stress,Mechanical Stresses,Stresses, Mechanical