Specific Aims and Experimental Design The specific aim of this pilot prospective interventional trial is to determine the feasibility/efficacy of treating cerebral oxygen desaturation in the ICU following cardiac surgery. Two groups of patients will be studied. Both groups will have cerebral saturation measured continuously both intraoperatively and postoperatively. The control group however, will have these measurements blinded to the intraoperative and postoperative caregivers. The interventional group will have the cerebral oximetry measurements available to the intraoperative and postoperative care team allowing them to intervene when a desaturation event occurs. If a cerebral desaturation occurs, defined as a decline in saturation of 10% from the patient's preoperative baseline, then a previously utilized interventional algorithm, NORMOSAT (B2012:005), will be instituted to reverse the decrease in cerebral saturation, ideally preventing it from becoming a clinically meaningful desaturation (previously defined by others as saturation decline of 25% from the baseline). The algorithm used addresses many of the known causes of desaturation, including low arterial oxygen content (both saturation and hemoglobin) and cardiac output influences on cerebral blood flow. As such, if a desaturation occurs, the patient will first have the PaO2 increased by increasing the inspired oxygen content. The PaCO2 will also be normalized by adjusting the ventilator settings. The cardiac output will be optimized and the blood pressure will be increased with standard ICU protocols to administer phenylephrine. If remaining low, the patients will be transfused to standard of care hemoglobin levels.