Postoperative cognitive dysfunction is a very common event after cardiac surgery, especially in elder patients and with lower education levels. The prevention of POCD should be done using a few simple features before surgery and during surgery, such as corticosteroids before surgery to reduce inflammation of the brain, which affect cognition. When possible, the anesthetic technique must be performed using the bispectral index (BIS) for controlling the length and depth of surgical anesthesia. The use of anesthetics that cause less damage in cognition in relation to other drugs that are already established as POCD trigger can also be the best way. The use of imaging tests that facilitate the research of cognitive disorders such as the use of structural and functional MRI or EEG for the accuracy of the survey brain region affected and that affected functions are good resources for cognitive rehabilitation. The cognitive rehabilitation techniques are very diversified as the use of digital games and activities that stimulate neuropsychological functions. The use of direct electrical current stimulation (tDCS) or of other electrical stimulation techniques can help the patient on rehabilitation of cognitive functions during the postoperative period.