Is Dexmedetomidine Associated With a Lower Incidence of Postoperative Delirium When Compared to Propofol or Midazolam in Cardiac Surgery Patients

Inclusion Criteria:

1. Diagnosis of a coronary artery disease, cardiac valve disease, or vascular problems requiring elective surgical intervention
2. Age older than 18 years of age, less than 90 years of age
3. Fluency in English, and willingness to participate in the study
4. No history of recent (< 3 months) of alcohol or drug abuse
5. No pre-operative evidence of heart block
6. No history of dementia, schizophrenia, or post-traumatic stress disorder

Exclusion Criteria:

1. A preexisting diagnoses of dementia, schizophrenia, active or recent alcohol or drug abuse/dependence; post-traumatic stress disorder; acute intoxication (i.e., positive urine drug and/or alcohol test at the time of initial evaluation or upon hospitalization for surgery)
2. Age younger than 18, or older than 89 years of age
3. Inability to understand enough English to complete required diagnostic testing
4. Unwillingness to participate in the study
5. Inability of subject or surrogate to consent.
6. Pregnancy