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Mechanics of ventilation. How the lung is supported and moved. Pneumothorax of right lung. ribs. Rotation axis. insp. exsp. Air flow. Static recoil. Interpleural pressure. Tidal volume. Interpleural pressure. ↓ C L. P = P. P=T/r. ↓T. ↑r.
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Mechanics of ventilation How the lung is supported and moved
ribs Rotation axis
insp exsp Air flow Static recoil Interpleural pressure Tidal volume Interpleural pressure
↓CL P = P P=T/r ↓T ↑r Dipalmitol fosfatidil cholin + protein
Alveoli are larger at the apex (upper panel) than base (lower)
∆V C = ∆V / ∆P ∆P
∆P . R=∆P / ∆V . ∆V
0.5 μm Gas Membrane blood
Limitation by perfusion Limitation by diffusion
Respiration at the limit: surviving on the summit of Mt Everest
Polycythemia at 4600 m altitude Hemoglobin concentration 19.8 g/dl Arterial PO2 45 mm Hg O2 saturation 81% O2 concentration 22.4 ml/dl
DLO2 = VO2 / PAO2 Pc O2 DLCO = VCO / PACO Time of blood flow through pulmonary capillary