Effects of dexmedetomidine on hemodynamics and stress reaction in pediatric patients with congenital heart disease undergoing open heart surgery with cardiopulmonary bypass

Objective To evaluate the effects of dexmedetomidine infusion on hemodynamic and stress reaction in pediatric patients with congenital heart disease undergoing open heart surgery with cardiopulmonary bypass.Methods Thirty pediatric patients undergoing open heart surgery with cardiopulmonary bypass, ASA class Ⅱ or Ⅲ, were randomly assigned to two groups: the group DEX (group D, n=15) and the group control (group C, n=15). Patients in group D received an initial bolus dose of dexmedetomidine (1.0 μg/kg) over 10 minutes, immediately followed by a continuous infusion of 0.5-1.0 μg·kg-1·h-1 until the end of the operation. The same volume of normal saline was given in the control group. Hemodynamic parameters and concentrations of blood glucose, cortisol, norepinephrine and epinephrine were measured before injection(T0), 10 min and 15 min after administration(T1 and T2), after incision(T3), after sternum saw (T4), after CPB(T5) and immediately after surgey(T6).Results The values of HR, SBP, DBP and MAP decreased significantly at T1-T6 in group D, and were significantly lower than those in group C, especially at T2(P0.05). In both groups, blood glucose,plasma cortisol, norepinephrine and epinephrine increased significantly at T4-T6. However, the values were lower in group D compared with those in group C(P0.05).Conclusion Intraoperative dexmedetomidine infusion attenuated the hemodynamic and neuroendocrinal response to surgical trauma and cardiopulmonary bypass in pediatric patients undergoing corrective surgery for congenital heart disease.