BIOL 2P93 Lecture Notes - Alveolar Pressure, Chronic Obstructive Pulmonary Disease, Asthma

• School: Brock University
• Department: Biological Sciences
• Course: BIOL 2P93
• Professor: Jenny Janke

Document Summary

Properties of elastic structures: terms, elastic structures, static mechanics relationship between pressure & volume in lung, dynamic mechanics relationship between pressure & flow in lung, volume is proportional to pressure, transmural pressure difference in pressure across the wall of the lung. Calculating ptm in respiratory system: palv = alveolar pressure, ppl = pulmonary pressure, pl = transpulmonary pressure = palv - ppl, pbs = body surface pressure (can be considered 0 b/c us. = atmospheric p: pcw = pressure of chest wall = ppl pbs, prs = pressure of respiratory system = palv - pbs. * negative pleural pressure => relaxed chest wall gets smaller. * mm. activation => negative pl. pressure => thorax enlarges: at high volumes, lung becomes stiff b/c elastic recoil increases, pressure-volume curve of lung. Determinants of lung volumes: tlc determined by total respiratory system p-v relationship & max negative pressure (tlc determined by strength of respiratory mm. In adults, occurs when sm. airways close off.