Dexmedetomidine is a unique sedative anesthetic agent that allows accurate control of the depth of sedation and provides analgesia, cardio protection, renal protection, and neuroprotection without causing respiratory depression. It is an alpha 2-adrenoreceptor agonist that modulates the release of catecholamines from the central and autonomic nervous systems. When patients sedated by dexmedetomidine are allowed to become responsive, they are calm and cooperative (1). No other sedative agent has this feature, and sedated patients frequently awaken in a confused state. Investigators are conducting this study project to compare between dexmedetomidine based and propofol based anesthetic techniques with regard to hemodynamic changes, stress hormone release as well as cytokines in patients undergoing CPB for coronary revascularization.

100 patients undergoing elective CPB for coronary revascularization surgery. On the morning of operation the patients were randomized to receive one of two anesthetic techniques dependent on the type of sedation used. Standard anesthetic technique will be used for all patients except for using dexmedetomidine sedation in one group and propofol sedation in the other group.

Inclusion Criteria:

• patients scheduled for elective coronary revascularization surgery with cardiopulmonary bypass

Exclusion Criteria:

• Severely impaired left ventricular function (ejection fraction <40%)
• Valvular heart disease
• Low cardiac output syndrome
• Uncontrolled rapid atrial fibrillation
• On plavix less than one week
• Severe systemic non-cardiac disease
• Infectious disease
• Poorly controlled diabetes mellitus
• patients on corticosteroids or other immunosuppressive treatment