Overview
A supported mean arterial pressure can coexist with very little pulse pressure. The pleth is reduced accordingly rather than showing a normal pulse waveform solely because total supported output is adequate.
Oxygenation and pulsatility are separate properties. A displayed modeled oxygen status is not proof that a real pulse oximeter could obtain a reliable measurement from a nonpulsatile extremity.
V-A ECMO regional mixing and differential upper-body hypoxemia are not fully predicted. Use the device notes and flow accounting when teaching those limitations.