Ventilation and Compliance 1 Flashcards
What is the capacity of each lung?
3L (total capacity of 6L)
What is the size of a typical breath?
500ml
How full are lungs at the end of a normal breath?
Half full
What is the volume of air that cannot be voluntarily shifted called?
Residual volume
How large is residual volume?
1.2L
What is residual volume needed for?
Stop alveoli from collapsing and for gas exchange to take place between breaths
How much gas is in anatomical dead space?
150ml
What is tidal volume?
A normal breath, 500ml
What is the volume of air breathed in or out of the lungs at each breath called?
Tidal volume, TV
What is expiratory reserve volume, ERV?
Maximum volume of air which can be expelled from the lungs at the end of a normal expiration
What is the maximum volume of air which can be expelled from the lungs at the end of normal expiration called?
Expiratory reserve volume, ERV
What is inspiratory reserve volume, IRV?
Maximum volume of air which can be drawn into the lungs at the end of a normal inspiration
What is the maximum volume of air which can be drawn into the lungs at the end of a normal inspiration called?
Inspiratory reserve volume, IRV
What is residual volume, RV?
Volume of gas in the lungs at the end of a maximal expiration
What is the volume of air in the lungs at the end of a maximal expiration called?
Residual volume, RV
What is vital capacity, VC?
Total volume + inspiratory reserve volume + expiratory reserve volume
What does total volume + inspiratory reserve volume + expiratory reserve volume make?
Vital capacity, VC
What is total lung capacity, TLC?
Vital capacity + residual volume
What does vital capacity + residual volume make?
Total lung capacity, TLC
What is inspiratory capacity, IC?
Tidal volume + inspiratory reserve volume
What does tidal volume and inspiratory reserve volume make?
Inspiratory capacity, IC
What is functional residual capacity, FRC?
Expiratory reserve volume + residual volume
What does expiratory reserve volume + residual volume make?
Functional residual capacity, FRC
What is FEV1?
Forced expired volume in 1 second
What is the forced expired volume in 1 second called?
FEV1
What is FEV1:FVC?
Fraction of forced vital capacity expired in 1 second
What is ventilation?
Movement of air in and out of the lungs
What are the 2 kinds of ventilation?
Pulmonary (minute) ventilation
Alveolar ventilation
What is pulmonary (minute) inspiration?
Total air movement into/out of lungs
What is alveolar ventilation?
Fresh air getting to alveoli and available for gas exchange
Which of pulmonary and alveolar ventilation is functionally significant?
Alveolar ventilation as it describes fresh air available for gas exchange
What is pulmonary and alveolar ventilation measured in?
L/min
How efficient is normal breathing and why?
70% because 150ml of the 500ml breath gets stuck in anatomically dead space
What is hyperventilation?
Breathing more air than normal (above 4.2L/min)
What is hypoventilation?
Breathing less air than normal (below 4.2L/min)
What is a standard value for alveolar ventilation?
4.2L/min
How does breathing less volume quicker compare to breathing larger breaths slower?
Both have the same pulmonary ventilation
More volume and slower has greater alveolar ventilation due to anatomically dead space during each breath having a smaller effect overall
What is Dalton’s law?
Total pressure of a gas mixture is the sum of the individual gasses
What is the air composed of?
78% nitrogen
21% oxygen
- 9% argon
- 04% carbon dioxide
What is carbon dioxide in our cells due to?
Carbon dioxide that we produce internally as waste, not the carbon dioxide that we breathe in
What is a partial pressure?
Pressure of a gas in a mixture of gases is equilvalent to the percentage of that particular gas in the entire mixture multiplied by the pressure of the whole gaseous mixture

How does the pressure exerted by different gas molecules compare?
All gas molecules exert the same pressure
What is normal atmospheric pressure?
101kPa
760mmHg
What are the partial pressures of oxygen and CO2 like under normal conditions?
Resting alveolar PCO2 and PO2 remains fairly constant

What happens to the partial pressures of oxygen and CO2 during hyperventilation?
PO2 rises and PCO2 falls
What happens to the partial pressures of oxygen and CO2 during hypoventilation?
PO2 falls and PCO2 rises