Ventilation and Compliance Flashcards
What is tidal volume?
Volume during normal breathing- 500ml
What is expiratory reserve volume?
Air that can be forced out of the lungs but not expelled during normal breathing- 1100ml.
What is residual volume?
Air always present in the lungs- we cannot expel- 1200ml.
Inspiratory Reserve Volume?
Extra air we can inhale on top of tidal volume- 3000ml.
What does the term capacity mean?
This shows that it is two or more volumes combined.
Name two capacities that we can measure.
Inspiratory Capacity- normal exhale and big breath in. (TV + IRV = 3500ml)
Vital Capacity- breath out as much as possible then breath in as much as possible. ( VT + IRV+ ERV= 4600ml)
Which capacity can we not measure?
Functional Residual Capacity. Because it includes the RV which cannot be measured.
Total Lung Capacity
Vital Capacity + RV
Around 5l
What is FVC
Forced Vital Capacity
How much air can you expel. (peak flow)
What is FEV1
The proportion of your FVC that can be expelled within 1 second.
What is the difference between pulmonary ventilation and alveolar ventilation?
Pulmonary- total air in/out of lungs.
Alveolar- FRESH air reaching the alveoli.
Define Partial Pressure
The pressure of a gas in a mixture is equivalent to what percentage of the mixture it makes up multiplied by the pressure of the entire mixture.
Find the partial pressure of oxygen in air. Oxygen - 21% and air - 760mmHg
PP= 0.21*760
=160mmHg
Define Compliance
Shows the stretchiness of the lungs- but not how well they recoil (elasticity)
Give an example of low compliance.
Big decrease in Intra-pleural pressure, but only small increase in lung volume- Fibrosis.
