Fig. 5.

Representative example of simultaneous trends in Compliance (ml/cmH₂O), CO₂ elimination per breath (ml), airway pressure (Paw, cmH₂O), transpulmonary pressure (PTP, cmH₂O) and ORI values of a patient during a recruiting maneuver (RM). While Paw rises in steps at the beginning of the RM, PTP and compliance rise accordingly and ORI increases up to a maximum value. Increases of dead space due to distention reduces the CO₂ elimination per breath. During the decremental PEEP trial, step-reductions in Paw and PTP do not reduce compliance or ORI values until a closing point is observed. The dotted arrow shows this point in which an abrupt drop in compliance and ORI coincide with a negative value of TPT indicating re-collapse of the lung. The optimal PEEP corresponds to the previous setting