Effect of different pressure-targeted modes of ventilation on transpulmonary pressure and inspiratory effort

Spontaneous breathing during mechanical ventilation improves gas exchange and might prevent ventilator-induced diaphragm dysfunction. In pressure-targeted modes, transpulmonary pressure (PL) is the sum of pressure generated by the ventilator and muscular pressure. When inspiratory effort increases, PL and tidal volume (VT) increase, potentially resulting in lung injury. This effect depends on the degree of inspiratory synchronization (i-sync); pressure-targeted modes can be classified into fully, partially, and non i-sync modes. A bench study [1] demonstrated that non-i-sync mode resulted in lower PL and VT than other modes, protecting the lungs from injury. We undertook to assess the effect of varying synchronization during pressure-targeted ventilation in critically ill patients.