Effects of dexmedetomidine on anesthesia with target controlled infusion of propofol and remifentanyl in patients undergoing thyroidectomy

Objective To investigate the effects of dexmedetomidine on anesthesia with target controlled infusion(TCI) of propofol and remifentanyl in patients undergoing thyroidectomy.MethodsForty adult patients scheduled for selective thyroidectomy were anaethetized with propofol and remifentanyl TCI,who were equally randomized into two groups of A(infused dexmedetomidine 1 μg/kg in 50 ml normal saline at 45 min before the end of operation)and group B(infused normal saline 50 ml as the control).The mean arterial pressure(MAP) and heart rate(HR) were monitored during anesthesia and at different BIS values of 60,70 and 80.The propofol target concentration and the recovery time from anesthesia were recorded as well.Results The effective-site target concentrations of propofol during recovery period were significantly lower in group A than those in group B(P0.01).The recovery time of group A was(21.0±6.6) min,which was longer than(15.5±3.3) min in group B(P0.05).Conclution Dexmedetomidine 1 μg/kg infused during TCI of propofol and remifentanyl can reduce the effective-site target concentrations of propofol,but prolong the recovery time from anesthesia in patients undergoing thyroidectomy.