Fig. 2 (abstract P249).

Oxygen partial pressure responsible for the hypoxic pulmonary vasoconstriction inhibition in four different clinical scenarios. The dotted line at PstimulusO2 of 19.2 mmHg represents the partial pressure during breathing of a healthy person. The other clinical scenarios reproduce mechanical ventilation in a severe ARDS patient with hypercapnia, pulmonary shunt fraction of 45%, and PvO2 = 20 mmHg (closed triangle); the closed squares represent this same patient after ECMO initiation, when the pulmonary shunt increased to 60% (Whitening-up phenomenon) and the PvO2 increased to 180 mmHg; at last, the open circles represent this same patient with a pulmonary shunt of 95% and a PvO2 of 300 mmHg