US study of gliding in nondependent lung regions: the dark side of the moon

A protective ventilatory strategy should prevent VILI, but in patients with larger nonaerated areas hyperinflation may occur during tidal ventilation even during a protective ventilatory strategy [1]. The gliding sign is used as a marker of pneumothorax and, in a study [2], to quantify preoperatively the degree of pleural adhesion in thoracic surgery patients. In our study we measured the variations of gliding (G) and static compliance (Cstat) according to incremental/ decremental variations of PEEP in patients with hypoxic respiratory failure.