ABSTRACT
Key physiological principles MV works by: • supporting/manipulating gas exchange by alveolar ventilation and oxygenation; • increasing lung volume by augmenting FRC; • reducing work of breathing by unloading the ventilatory muscles. The main physiological difference between MV and spontaneous respiration is that during spontaneous respiration a subatmospheric pressure is generated during inspiration, which entrains air into the lungs, whereas, with MV this is replaced by a positive pressure forcing gas into the lungs.
