Biomaterial Database

Pleural liquid pressure in the zone of apposition and in the lung zone. 1989

E Agostoni, and P G Agostoni, and L Zocchi

Istituto di Fisiologia Umana I, Università di Milano, Italy.

Pleural liquid pressure in zone of apposition (Pliq,ap) and in lung zone (Pliq,L) was measured simultaneously through liquid filled cannulas in anesthetized dogs in lateral posture. At top Pliq,ap and Pliq,L at iso-height were -9.7 +/- 0.4 and -11.9 +/- 0.3 cm H2O, respectively, at end expiration (eE; P of delta less than 0.01; 11 dogs); -9.6 +/- 0.7 and -19.8 +/- 0.7 cm H2O at end inspiration (eI). At bottom they were -0.6 +/- 0.2 and -2.4 +/- 0.4 cm H2O, respectively, at eE (P of delta less than 0.05; 4 dogs); -1.5 +/- 0.3 and -8.5 +/- 1.0 cm H2O at eI. Vertical gradient of Pliq,ap was -0.97 +/- 0.02 cm H2O/cm. A 132% increase in ventilation (after 10 min dead space breathing) did not change eE and eI Pliq,ap, and eE Pliq,L, but decreased eI Pliq,L. These results imply: (1) no transmission to zone of apposition of tidal changes in Pliq,L; (2) a liquid flow from zone of apposition to lung zone; (3) a net filtration into zone of apposition. They suggest that absorption pressure of capillaries of visceral pleura is greater than that of lymphatics of zone of apposition. Lymphatic role in setting Pliq,L is discussed.

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
D010994	Pleura	The thin serous membrane enveloping the lungs (LUNG) and lining the THORACIC CAVITY. Pleura consist of two layers, the inner visceral pleura lying next to the pulmonary parenchyma and the outer parietal pleura. Between the two layers is the PLEURAL CAVITY which contains a thin film of liquid.	Parietal Pleura,Visceral Pleura,Pleura, Parietal,Pleura, Visceral
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
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