Ensure an "Ultrasound Window" on the Patient's Neck to Evaluate Cerebral Blood Flow!

Near-infrared spectroscopy (NIRS) does not provide information about changes in oxygenation in whole-brain areas. Although the branching vessels of the aortic arch are not always easy to identify using transesophageal echocardiography (TEE), the blood flow status of cervical arteries can always be assessed by applying an ultrasound probe via the "ultrasound window" on the patient's neck, which can be ensured by devising alternative insertion approaches of the central venous catheter. This method is very simple but compensates for the limitations of the combination of NIRS and TEE, especially during cardiac surgery with cardiopulmonary bypass management using selective cerebral perfusion.