- 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 o Protective against ventilator-associated lung injury – less cyclical atelectasis and alveolar overdistension· Less lung deformation o Less compression of the lungs by the heart (which sits on the sternum in the prone position) o Less compression by the abdominal content. · Improved drainage of secretions: o The orientation of large airways apparently enhances the drainage of respiratory secretions and aspirated material· Improved mechanics of the chest wall in obesity
