A Research Study to Evaluate the Effectiveness of Dexmedetomidine in Preventing Delirium After Heart Surgery

Exclusion Criteria

• •Cognitive function level by Mini Mental State Exam (MMSE) of ≤ 20 at screening.
• •Subject has a positive CAM-ICU result for delirium at Screening.
• •Subject requires chronic anti-psychotic therapy.
• •Subject has participated in a trial with any experimental drug or experimental implantable device within 30 days prior to the study drug administration, or has ever been enrolled in this study.
• •Subject is known to be in liver failure.
• •Subject has an anticipated potential for increased intracranial pressure or an uncontrolled seizure disorder or known psychiatric illness that could confound a normal response during study assessment.
• •Subject has acute myocardial infarction, HR \<50 bpm, SBP \<90 mmHg, is hemodynamically unstable requiring systemic inotropic drugs or intra-aortic counterpulsation balloon pump within the last 72 hours.
• •Subject is anticipated to require hypothermic circulatory arrest during this surgical procedure.
• •Subject has received treatment with a α2-agonist or antagonist (within 14 days of study entry).
• •Subject for whom opiates, propofol, Dexmedetomidine or other α2-agonists are contraindicated.
• •Subject has, per the investigator's judgment, a known or suspected physical or psychological dependence on an abused drug, other than alcohol.
• •Subject has any condition or factor which, in the Investigator's opinion, might increase the risk to the subject.
• •Subject is not expected to live more than 60 days.