The myocardial protective effect of dexmedetomidine in high-risk patients undergoing aortic vascular surgery

OBJECTIVE The aim of the study was to assess the effect of dexmedetomidine in high-risk patients undergoing aortic vascular surgery. DESIGN A randomized prospective study. SETTING Cairo University, Egypt. MATERIALS AND METHODS The study included 150 patients undergoing aortic vascular surgery. INTERVENTION The patients were classified into two groups (n = 75). Group D: The patients received a loading dose of 1 μg/kg dexmedetomidine over 15 min before induction and maintained as an infusion of 0.3 μg/kg/h to the end of the procedure. Group C: The patients received an equal volume of normal saline. The medication was prepared by the nursing staff and given to anesthetist blindly. MEASUREMENTS The monitors included the heart rate, mean arterial blood pressure, central venous pressure, electrocardiogram (ECG), serum troponin I level, end-tidal sevoflurane, and total dose of morphine in addition transthoracic echocardiography to the postoperative in cases with elevated serum troponin I level. MAIN RESULTS The dexmedetomidine decreased heart rate and minimized the changes in blood pressure compared to control group (P < 0.05). Furthermore, it decreased the incidence of myocardial ischemia reflected by troponin I level, ECG changes, and the development of new regional wall motion abnormalities (P < 0.05). Dexmedetomidine decreased the requirement for nitroglycerin and norepinephrine compared to control group (P < 0.05). The incidence of hypotension and bradycardia was significantly higher with dexmedetomidine (P < 0.05). CONCLUSION The dexmedetomidine is safe and effective in patients undergoing aortic vascular surgery. It decreases the changes in heart rate and blood pressure during the procedures. It provides cardiac protection in high-risk patients reflected by decreasing the incidence of myocardial ischemia and serum level of troponin. The main side effects of dexmedetomidine were hypotension and bradycardia.