Respiratory Mechanics Flashcards
How does air move relative to pressure?
Air moves from high pressure to low pressure… like blood!!
What keeps the lungs from collapsing?
intrapleural pressure, which always stays negative and “pulls” the lungs open
What structure keeps the lungs from getting too small?
Ribs–fixed minimum volume structure
How does exercise affect pulmonary pressures?
More muscle (diaphragm, intercostal) activation drives deeper inhalation, increases lung volume -> decreases intrapleural pressure
What is atmospheric pressure?
760mmHg at sea level, referred to as 0mmHg for standard
What is trans-pulmonary pressure?
Recoil of the lungs/collapsing force; 4mmHg (relative to AP)
What is intrapleural pressure?
Pressure of expansion by pleura; ranges from -2mmHg during exhalation to -6mmHg during inhalation (relative to AP)
What is alveolar/intrapulmonary pressure?
pressure within the alveoli. Net pressure between pleural and trans-pulm; ranges from -2 to 2 mmHg (relative to AP)
