文档介绍：12 November 2008
Respiratory Physiology
Mostly white board diagrams in class today covering:
5L blood over tennis court = huge surface area for gas exchange.
Ventilation = movement of air by bulk flow in response to pressure gradients (Boyle’s law) (Atmospheric and alveolar pressures)
Gas exchange by diffusion.
Tidal Inspiration is active (requires muscle contraction of diaphragm and intercostal muscles.) Tidal expiration is passive (elastic recoil of lung tissue.)
Compliance (opposite of stiffness) is influence by surface tension in alveoli (governed by Law of Laplace) and altered by surfactant which reduces surface tension and pliance.
Figure
Type II pneumocytes secrete surfactant.
Gas exchange by diffusion based on gradients.
Figure
Pneumothorax (unilateral due to each lung having its partment.
Greg R. and the story of spontaneous pneumothorax
Visceral pleura and parietal pleura separated by fluid-filled pleural cavity which allows lung and chest wall to slide relative to each other but remain adhered unless air enters the pleural cavity (which leads to collapse of the lung and outward expansion of c