The effect of esmolol on the QTc interval during tracheal intubation in elderly patients with coronary artery disease

Objective To evaluate the effect of esmolol on the QTc interval during tracheal intubation after anesthesia induction in elderly patients with coronary artery disease.Methods Fifty patients aged 60-75y with ASA II were randomly allocated either to esmolol(E) or to control(C) group.A bolus of 0.3 mg/kg esmolol was administered to the group E and followed by a continuous infusion at a rate of 100 μg·kg-1·min-1;group C received same volume of saline.The changes in QTc,MAP and HR were recorded at following time points: prior to anesthesia induction(T0),2 min after esmolol or saline injection(T1),1 min following fentanyl and propofol delivery(T2),3 min after vecuronium given(T3),30 s(T4),2 min(T5) and 4 min(T6) after intubation.Results QTc interval was enlarged significantly after intubation at T4,T5 and T6 than that of at T0(P0.05),and this effect was far greater in the group C than the group E(P0.01),and the number of patients with QTc intervals440 ms were more in the control group than the esmolol one(P0.05).Conclusion QTc interval enlarged following tracheal intubation during induction of anesthesia in elderly patients with coronary artery disease,but esmolol can attenuate such change in the QTc interval associated with tracheal intubation.