Gas exchange

Question 1

For effective gas exchange to occur, the alveoli must be adequately ventilated and perfused.

What is Ventilation and perfusion

Answer 1

Ventilation (V) refers to the flow of air into and out of the alveoli.

Perfusion (Q) refers to the flow of blood to the alveolar capillaries

Question 2

collective changes of ventilation and
perfusion in the lungs are measured clinically. How?

Answer 2

using the ratio of V/Q

Question 3

V/Q Mismatch can occur in the following situations:

Answer 3

Increased alveolar dead space
Congenital heart defects with right-left shunts (they may reduce/bypass pulmonary circulation)
Asthma (bronchoconstriction decreases ventilation)
Pulmonary embolism results in restricted blood flow to pulmonary circulation

Question 4

What is resistance and how do you calculate it

Answer 4

The friction caused by movement of
air throughout the respiratory system

Resistance is change in pressure
divided by flow.

Question 5

Compliance and how to calculate it

Answer 5

The lungs ability to stretch and expand

Compliance is volume divided by change in pressure.