Flashcards in Lecture 5 - Mechanics of Ventilation Deck (10):
Only condition of inspiration?
Alveolar pressure is lower than barometric pressure
Intrapleural pressure is always?
Hookes Law in 1D and 3D?
1: Force proportional to change in length; 3D: change in volume proportional to change in pressure
Components of lung compliance?
Tissue compliance, air-water surface tension, atelectasis
Saline filled lungs vs air filled?
More compliant (less pressure) due to lack of air-water surface tension
Laplace's Law? (bubbles)
Pressure proportional to tension/radius
Total Thoracic Compliance equation?
1/Ct = 1/C.lung + 1/C.CW
Influence of Gravity on Compliance?
Lower point of lung has higher pressure (less negative), causing the same change of pleural pressure to cause greater change of vlume than at higher point with less pleural pressure - i.e. greater compliance
Decreased pulmonary compliance - lung pathologies?
pulmonary fibrosis, alveolar oedema, elevated pulmonary venous blood pressure, atelectasis, surfactant deficiency