Answer:
- Gravity
- Body position
Step-by-step explanation:
Ventilation is defined as the exchange of air between atmosphere and the lungs so that the carbon dioxide in the alveoli (the small gas sacs in the lungs) can be exchanged.
Factors affecting distribution of air in respiratory system while ventilation are as following:
- Gravity: Total blood flow and alveolar ventilation in the dependent lung is lower than in the non-dependent lung in the left lateral location, since the drop in lung volume outweighs any gravity-dependent ventilation and perfusion increases.
- Body position: Changing position is necessary to break through the daily monotonic delivery of mechanical ventilation and favour the clearance of respiratory secretions and results in the improvement of lung volume and oxygenation.