PEEP and HFOV should be tailored on individual physiology. Assuming that the esophageal pressure is a good estimation of pleural pressure, transpulmonary pressure can be estimated by the difference between airway pressure and esophageal pressure (PL= Paw - Pes). A PL of 0 cmH2O at end-expiration should keep the airways open (even if distal zones are not certainly recruited) and a PL of 15 cmH2O should produce an overall increase of lung recruitment.