“…If the changes in either pEEG monitoring or cerebral saturation are unilateral, and the peripheral or somatic NIRS saturation is normal, localized cerebral hypoperfusion should be suspected. Furthermore, cerebral investigation should be pursued, such as a carotid, jugular, and brain ultrasound, TCD, 15 optic nerve sheath measurement, 16,17 and/or computed tomography. On the other hand, if the cerebral saturation reduction is bilateral and symmetrical and the somatic NIRS saturation is also reduced, then a non-cerebral etiology such as cardiogenic shock, hemorrhagic shock, hypoxemia or obstruction to adequate central venous drainage (superior or inferior vena cava) is more likely, as previously reported.…”