Fig. 3.

Schematic drawing exemplifying dual circulation in V-A ECMO with severe pulmonary failure when draining from the IVC and reinfusing into the femoral artery. Although preoxygenator saturation is acceptable at 60–80%, the arterial saturation in the aortic arch may be 50–70% and SVC saturation as low as 20–40%. The SVC desaturation may be unnoticed since the venous blood drained to the ECMO circuit mainly originates from the IVC, where venous saturations usually show high normal values. OX oxygenator