Ventilation and Lung Mechanic

Question 1

What can cause a collapse lung.

Answer 1

1) Elastic recoil, elastic properties of the alveolar walls.
2) Surface tension, droplets in the alveoli = alveolar membranes drawn together = alveolar collapse.

Question 2

How can a collapse lung be prevented.

Answer 2

Collapsing is normally prevented by surfactant and intrapleural pressure.
Surfactant secreted by alveolar epithelium and consists of lipoproteins.

Question 3

How can air flow be examined

Answer 3

Pulmonary volumes

Pulmonary capacities

Question 4

What are the 4 pulmonary volumes

Answer 4

Tidal volume = volume of air that passes into and out of the lungs during normal inspiration and expiration. (500ml).
Inspiratory reserve volume = amount of air that can be inspired on top of the tidal volume. (3000ml).
Expiratory reserve volume = volume of air that can be exhaled forcefully (1100ml).
Residual volume. (1200ml).

Question 5

What are the pulmonary capacities

Answer 5

The pulmonary capacities are a measure of 2 or more pulmonary volumes combined.

1) Inspiratory capacity = 3500ml.
2) Functional residual capacity provides a measure of the total amount of air left in the lungs after a normal expiration (2300ml).
3) Vital capacity = total amount of air that can be exhaled after a maximal inspiration (4600ml).
4) Total lung capacity

Question 6

What is minute respiratory volume

Answer 6

Measure of the total volume of air that passes through the respiratory system per minute = 6L.