Mechanical Ventilation - clinical applications

Question 1

What is functional residual capacity?

Answer 1

Volume of air in the lungs at the end of quiet expiration

Question 2

How do bronchioles stay open in expiration?

Answer 2

Radial traction of the surrounding alveoli walls on bronchioles

Question 3

Briefly describe interstitial lung disease

Answer 3

Thickening of the pulmonary interstitium, reducing lung compliance and increasing elastic recoil

Question 4

What is the pulmonary interstitium?

Answer 4

The microscopic space between the alveolar epithelium and the capillary endothelium

Question 5

What 3 substances does interstitium contain?

Answer 5

Elastic fibre, collagen fibres and fibroblasts

Question 6

Briefly describe Neonatal respiratory distress syndrome

Answer 6

Preterm babies have a lack of surfactant, so increased effort is required to breath

Question 7

Briefly describe COPD

Answer 7

Caused by smoking and inhaled pollutants, all conditions share impaired airflow that is not fully reversible, e.g emphysema and chronic bronchitis

Question 8

Briefly describe chronic bronchitis

Answer 8

mucus hypersecretion and reduced cilia. Can cause stasis risking infection

Question 9

Briefly describe emphysema

Answer 9

Permanent enlargement of the air spaces, with destruction of alveolar walls and elastin

Question 10

Briefly describe Pneumothorax

Answer 10

When the pleura is breached, air flows from the atmosphere into the pleural cavity. Lung collapses as elastic recoil is not countered by negative pleural pressure