Group Q: will receive 25 mg quetiapine at night of surgery and 25 mg daily for 7 days postoperative (30 patients).~Group C: will receive placebo alone (30 patients). During the study period, enrolled patients will be assessed for delirium once daily (from 7:00 AM to 7:00 PM), and the assessment will be performed in two steps. First, level of sedation will be assessed using the RASS. If the patient will be deeply sedated or unarousable (RASS -4 or -5), the assessment will not be performed and the patient will be reassessed at a later time. If the patient has a RASS of -3to +4, then the assessment will be continued to the next step.~Second, delirium will be diagnosed using the CAM-ICU. The screening tool detects four features of delirium: acute onset of mental status change or a ﬂuctuating course, inattention, disorganized thinking, and altered level of consciousness. To have delirium diagnosed, a patient displays the ﬁrst two features with either the third or fourth feature.~The primary outcome is delirium incidence diagnosed with the CAM_ICU within the study period. If the CAM_ICU is positive at least once during the study period, it will be recorded that a delirium occurred.~Secondary outcomes is the rate of positive CAM-ICU (the number of positive CAM-ICU counts/the number of total CAM-ICU counts), days without delirium (number of days from the start of treatment until delirium), the duration of delirium if it appear (number of days with delirium), severity of delirium as measured with delirium rating scale revised 98 (DRS-R-89), the length of stay in the ICU, the length of stay in the hospital, the duration of intubation, a successful extubation, the ICU mortality, the overall mortality, measurement of QTc prolongation, and the use of rescue medication.
low-dose quetiapine may be effective in preventing delirium in patients. The purpose of this study is to evaluate the efficacy and safety of quetiapine for delirium prophylaxis in cabg