Postoperative Clinical and Neurophysiological Assessment of Patients After Open Heart Surgery

The enrolled patients will undergo Digital Electroencephalography (DEEG) monitoring for at least two hours. A senior epileptologist will make a DEEG interpretation to detect DEEG abnormality. DEEG patterns will be categorized according to the American Clinical Neurophysiology Society's standardized critical care DEEG terminology(normal, slowing and asymmetry, sharp and wave, periodic discharges, ictal patterns burst suppression, and electrocerebral silence)