Lecture 30 Flashcards
______ is the exchange of air between the atmosphere and the lungs where gas exchange with the blood occurs.
Ventilation
_________ requires that P-alv < P-atm, (negative value), so air flows in.
Inhalation
__________ requires that P-alv > P-atm, (positive value), so air flows out.
Exhalation
Actual air flow is also dependent on the resistance of the airways to flow which is primarily due to airway _______ which is affected by the ANS.
diameter
Inflation/deflation of the lungs is due to _______ vs compliance (“stretchability”)
transpulmonary pressure (Ptp)
The _______ is the pressure difference between the alveoli and the intrapleural fluid and is defined as Palv - Pip
transmural pulmonary pressure (Ptp)
The _______ is the pressure difference between the intrapleural fluid and the atmosphere and is defined as Pip - Patm
transmural chest wall pulmonary pressure (Pcw)
Overall, the ________ is the pressure difference between the alveoli and the atmosphere and is defined as Palv - Patm: combination of Ptp and Pcw
transmural respiratory system pressure (Prs)
Ptp is a determinant of _____ and Prs determines _____ (ignoring R/resistance to flow/airway diameter)
lung size; flow
_______ requires muscle contraction to ↑volume of thorax causing ↓Pip/more negative.
Inspiration
Ptp becomes more positive, it means the lungs are ______
expanding
T or F?During inspiration various muscles contract to ↑volume of thorax and therefore ↓Pip.
True
What is tidal volume (TV)?
Amount of air inhaled or exhaled in one breath during relaxed, quiet breathing. (~500mlml)
What is inspiratory reserve volume (IRV)?
Amount of air in excess of tidal inspiration that can be inhaled with maximum effort. (~3200ml)
What is expiratory reserve volume (EVR)?
Amount of air in excess of tidal inspiration that can be exhaled with maximum effort. (~1200ml)