The Effects Of Dexmedetomidine On QTc And Tp-e Interval In Diabetic Patients During Induction Of General Anesthesia

Objective: To explore the effects of dexmedetomidine on QTc and Tp-e interval in diabetic patients during induction of general anesthesia.Methods: 60 cases of patients with diabetic mellitus(DM)were scheduled to undergo induction of general anesthesia.ASA?~? grade,age 40~70 years old,Body Mass Index(BMI)18~30 kg/m2,the duration of diabetic more than one years,the glycemia of preoperative was no more than 11.2 mmol/L.Patients were randomly and equally arranged into 2 groups: dexmedetomidine group(group D,n=30)and normal saline group(group C,n=30),The Patients in group D were received the intravenous infusion of dexmedetomidine 0.5 ug/kg as a loading dosage in 10 min before anesthesia induction,which was followed by a continuous infusion of dexmedetomidine 0.4ug/kg/h until 3 min after intubation.while volume-matched normal saline were given instead as a placebo in group C.The change of HR,MAP,QTc interval and Tp-e interval were recorded and analyzed at baseline before dexmedetomidine administration(T0),before tracheal intubation(T1),and after tracheal intubation 1 min(T2),2 min(T3),3 min(T4).Results:(1)QTc interval and Tp-e interval: When compared with T0,in group D,QTc interval and Tp-e interval values at T1-T4 were no significant differences(P >0.05),QTc interval values at T2 as Tp-e interval values at T1 and T4 were prolonged signifcantly in group C(P <0.05).When compared with group C,QTc interval values at T1,T2 and T4 as Tp-e interval values at T1-T4 in group D were signifcant lower(P<0.05).The QTc intervals and Tp-e interval values returned to baseline around within 3 minutes after tracheal intubation in both groups.(2)Hemodynamic : When compared with T0,in group D,HR was lower at T1,T3 and T4 as MAP was lower at T1-T4(P<0.05);when compared with T1,in group D,HR at T2 and T3 as MAP at T2-T4 were increased signifcantly(P<0.05).When compared with T0,in group C,HR was significant differences at T1,T2 and T4 as MAP was lower at T1,T3 and T4(P<0.05);when compared with T1,in group C,HR at T2-T4 as MAP at T2 and T3 were increased signifcantly(P<0.05).When compared with group C,HR and MAP in group D were lower at T2(P<0.05).Conclusion: dexmedetomidine administration can effectively inhibit the response of tracheal intubation and maintain hemodynamic stability in diabetic patients during induction of general anesthesia.it also can signifcantly prevent the prolongation of QTc and Tp-e interval during induction of general anesthesia from reducing the risk of severe arrhythmia in diabetic patients.