- Improved V/Q matching (probably most important factor)
- More uniform distribution of ventilation and perfusion
- Prevents atelectatic bases receiving highest blood flow
- A relative increase in functional residual capacity
- Reduction of cephalad pressure on the diaphragm
- Reopening of atelectatic segments
- More homogeneous ventilation:
- Reduces the difference between the dorsal and ventral pleural pressure
- Protective against ventilator-associated lung injury – less cyclical atelectasis and alveolar overdistension
- Less lung deformation
- Less compression of the lungs by the heart (which sits on the sternum in the prone position)
- Less compression by the abdominal content. ·
- Improved drainage of secretions:
- The orientation of large airways apparently enhances the drainage of respiratory secretions and aspirated material
- Improved mechanics of the chest wall in obesity
