Fig. 4. Individual and average ( horizontal bar ) values of arterial carbon dioxide partial pressure (Paco2) and arterial pH during acute respiratory distress syndrome network ( ARDSNet ) strategy after lowering tidal volume and before initiating carbon dioxide removal (baseline), and 60–90 min (T1.5), 24 h (T24), 48 h (T48), and 72 h (T72) after initiation of carbon dioxide removal. * P < 0.001 versus ARDSNet ventilation.