Pleural pressure was measured by a capsule placed in the superior part of right 8th or 9th intercostal space of dogs in left lateral posture. Transit of lung border was observed through endothoracic fascia at sides of the capsule. During inspiration the capsule membrane faced sequentially: diaphragm, lung border, lung; vice versa during expiration. Pressure on the diaphragm at end expiration was -5.3 +/- 0.5 cm H2O, reflecting outward recoil of the rib cage. At transit of lung border during inspiration (bor. I) a marked negative pressure spike occurred; a smaller spike occurred at expiratory transit (bor. E). These spikes should reflect pleural liquid pressure at lung border. At bor. I lung volume and radial displacement of rib 9 or 10 were greater during active than passive ventilation, whereas at bor. E they were similar under both conditions. Hence, during spontaneous inspiration displacement of lung border lags behind lung and rib expansion. Speed of lung border (assessed from duration of negative spike) ranged from 0.8 to 2.3 cm/sec during spontaneous breathing. On average it was similar at bor. I and bor. E, while air flow was greater at bor. I.
Pleural pressure from abdominal to pulmonary rib cage: sweep of the lung border / E. Agostoni, L. Zocchi, P. G. Agostoni, P. T. Macklem. - In: RESPIRATION PHYSIOLOGY. - ISSN 0034-5687. - 75:1(1989 Jan), pp. 105-15-115.
|Titolo:||Pleural pressure from abdominal to pulmonary rib cage: sweep of the lung border|
AGOSTONI, EMILIO (Primo)
ZOCCHI, LUCIANO ALDO MARIA (Secondo)
AGOSTONI, PIERGIUSEPPE (Penultimo)
|Parole Chiave:||Pleura; Animals; Ribs; Lung; Respiration; Dogs; Pressure; Lung Volume Measurements|
|Settore Scientifico Disciplinare:||Settore MED/11 - Malattie dell'Apparato Cardiovascolare|
|Data di pubblicazione:||gen-1989|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/0034-5687(89)90090-X|
|Appare nelle tipologie:||01 - Articolo su periodico|