Effect of dexmedetomidine on myocardial injury in infants undergoing repair of ventricular septal defect / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of dexmedetomidine on myocardial injury in infants undergoing repair of ventricular septal defect.Methods Forty ASA grade Ⅱ or Ⅲ infants,aged 3-6 months,weighing 4-6 kg,scheduled for elective repair of ventricular septal defect,were randomly divided into 2 groups (n =20each)control group (group C) and dexmedetomidine group (group D).Anesthesia was induced with midazolam,etomidate,cisatracurium and sufenanil.The infants were mechanically ventilated after nasotracheal intubation.PET CO2 was maintained at 30-40 mm Hg,Anesthesia was maintained with cisatracurium,sufenanil and sevoflurane.In group D,dexmedetomidine was infused at 0.5 μg· kg-1 · h-1 until the end of operation.While in group C normal saline was given at the same rate until the end of operation.BP and HR were recorded at 10 min before operation (T1),skin incision (T2),chest opening (T3),10 min after aortic unclamping (T4) and the end of operation (T5).Blood samples were taken from the right internal jugular vein for determination of plasma creatine kinase MB (CK-MB) activity and cardiac troponin T (cTnT) concentrations at T1,T5 and 24 h after operation (T6).Results Compared with the baseline value at T1,no significant changes were found in HR and BP at different time points in group D,HR and BP were significanfly increased at T2-T5 in group C,and the plasma CK-MB ctivity and cTnT concentration were significantly increased at T5 and T6 in the two groups (P ＜ 0.05).HR and BP at T2-5 and plasma CK-MB activity and cTnT concentration at T5 and T6 were significantly lower in group D than in group C (P ＜0.05).Conclusion Dexmedetomidine infused at 0.5 μg· kg-1 · h-1 after induction can reduce myocardial injury in infants undergoing repair of ventricular septal defect.