Respiratory ventilation, volumes and capacities Flashcards
Inspiratory reserve volume
IRV is air that is inhaled after tidal volume.
What is tidal volume?
Air that moves into lungs with normal respiration
Normally 500 mL
What is expiratory reserve volume?
ERV
Air that can be breathed out AFTER a normal expiration
What is Residual volume?
Air that is still in the lung after maximal expiration.
CANNOT BE MEASURED by spirometry.
What is inspiratory capactity?
Inspiratory reserve volume + Tidal Volume
What is functional residual capacity?
RV + ERV (expiratory reserve volume)
Volume of gas in lungs after a normal expiration
What is vital capacity?
TV + IRV + ERV
Maximum volume of gas that can be expired after a maximal inspiration.
What is total lung capacity?
IRV + TV + ERV + RV
Volume of gas present after maximal inspiration.
What is minute ventilation?
tidal volume x respiratory rate gives total volume of gas entering the lungs per minute.
At Functional residual capacity (FRC) what are the pressures in the chest?
Airway and alveolar pressures are 0
Intrapleural pressures are negative.
What is compliance?
Change in lung volume for a given change in pressure.
Decreased in pulmonary fibrosis, pneumonia, pulmonary edema, and increased in emphysema/normal aging.
Describe hemoglobin R vs T forms and O2 affinity
R form has high O2 affinity.
T form has low O2 affinity.
Why does fetal hemoglobin have more affinity for O2 than adults?
Fetal hemoglobin has a lower affinity for 2,3 BPG thus leads to more O2 affinity compared to adults.
Increased chloride, H+, CO2 and 2,3 BPG and temeprature has what effect on O2 affinity in the RBC?
Leads to favor of the T form leading to decreased O2 affinity.
