Surface Tension/Airway Resistance Flashcards
What effect does the surface tension of water have on alveoli?
Opposes alveolar expansion
Promote fluid accumulation in alveoli
Can collapse alveoli sending air into larger alveoli
What is the purpose of surfactant?
Counteracts surface tension (intercalates in water)
Increase lung compliance
Prevent collapse of small alveoli
Prevent fluid accumulation in alveoli
How does lung volume influence airway resistance?
Airway expansion causes decreased resistance and vice versa.
How does bronchial smooth muscle tone influence airway resistance?
Contraction narrows airways causing increased resistance
What is dynamic airway collapse?
Positive intrapleural pressure developing and causing collapse of airways. Can occur from forced expiration, or at inherently low pressure like those found in emphysema.
