[Effects of dexmedetomidine on perioperative cardiac adverse events in elderly patients with coronary heart disease].

To investigate the effects of dexmedetomidine on perioperative cardiac adverse events in elderly patients with coronary heart disease.
 Methods: Sixty elderly patients, who were diagnosed as coronary heart disease and underwent gastric cancer operation, were randomly divided into 2 groups (n=30): the dexmedetomidine group (Dex group) and the control group. In the Dex group, dexmedetomidine was administered intravenously at 0.5 μg/(kg·h) after a bolus infusion at 0.5 μg/kg for 10 min before anesthesia induction. In the control group, equal volume of normal saline was infused instead of dexmedetomidine. The 2 groups received the same anesthesia treatment. The venous bloods were collected at the preoperative 0 h and postoperative 24 h. The concentrations of cardiac troponin (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP) and hypersensitive C-reactive protein (hs-CRP) were determined. The ECG was monitored at the above time and the postoperative incidence of cardiac adverse events was recorded.
 Results: The levels of cTnI, NT-proBNP and hs-CRP in serum were elevated in the 2 groups after the operation. Compared with the control group, the levels of cTnI, NT-proBNP and hs-CRP were significantly decreased in the Dex group (P<0.05). Compared with the control group, the incidence of bradycardia were significantly increased, while the myocardial ischemia and tachycardia were significantly decreased in the Dex group during the operation (P<0.05); the incidence of silent myocardial ischemia and arrhythmia was significantly reduced at 3 days after operation in the Dex group (P<0.05).
 Conclusion: Dexmedetomidine could decrease the incidence of cardiac adverse events in elderly patients with coronary heart disease.