Effect of using low-dose Dexmedetomidine during tracheal extubation for elderly patients after general anesthesia

Objective To study the effect of using low-dose of dexmedetomidine during tracheal extubation in elderly patients recovering from general anesthesia. Methods Forty elderly patients,ASA Ⅰ ~ Ⅱ,scheduled for the surgery under general anesthesia,were participated in one of the two randomized trials: control group( group C,n = 20,NS group) and observation Groups( group D,n = 20,dexmedetomidine 0. 5 μg /kg). All patients received continuous monitoring of HR,BP and SPO2to detect the depth of anesthesia. After the induction of anesthesia,endotracheal intubation was performed and patients were given propofol and remifentanil given by target-controlled infusion( TCI) to maintain deep anesthesia,keep BIS between 40 and60,10 minutes before the end of surgery,patients in group D and group C were infused dexmedetomidine 0. 5μg/kg,and the same volume of normal saline,respectively,within 10 minutes. All the indicators closely monitored and recorded included: SBP,DBP,HR at every time-point. Time periods of experiment were recorded as follow: t1( time between the end of surgery to extubation),recovery time t2( the time after extubation until patients could manage instructional activity). Sedation was assessed by Ramsay Post treatment of reverse reaction caused by extubation was also closely recorded. Results HR in group D were significantly lower than that based on the numerical( P 0. 05). HR SBP and DBP in group C were significantly higher than based on the numerical and data of group D( P 0. 05). Conclusion Application of single infusion of 0. 5 μg / kg dexmedetomidine into eldly patients at extubation period can stabilize the hemodynamics,and would not prolong the extuabtion and recovery time.