The protective effect of dexmedetomidine on perioperative myocardial injury in aged hypertensive patients

Objective To determine the protective effect of dexmedetomidine on perioperative myocardial injury in aged hypertensive patients.Methods Sixty patients with hypertension ofⅡ degree,aged 65 year,undergoing hip replacement surgery were randomly divided into dexmedetomidine group(D) and control group(C) with 30 cases each.,In group D,dexmedetomidine was administered intravenously at 0.7μg.kg-1.h-1after a bolus infusion at 1 μg/kg for 10 min before anesthesia induction.Changes of HR,SBP,DBP and ST segment in ECG were monitored 10 minutes before anesthesia,immediately after intubation and extubation.The central venous blood samples were obtained to measure the expression of IMA(ischemia modified albumin) 10 minutes before anesthesia(TO),1h after skin incision(T1),at the end of operation(T2) and 12 h,24 h after operation(T3-4) in cobalt binding(ACB)test.Results HR,SBP,DBP in group D was lower than that of group C immediately after intubation and extubation;The cases with ST segment changes showing myocardial injury were significantly higher in group D than those in group C(7 VS 1)(P0.05).The expression of IMA in group C at T1,T2were obviously higher than that of group D(P 0.05).Conclusion Dexmedetomidine intravenously could attenuate the degree of myocardial damage in aged hypertensive patients undergoing hip replacement surgery.