The use of dexmedetomidine in pediatric cardiac surgery.

We tested dexmedetomidine, an alpha2 agonist, for its ability to decrease heart rate, arterial blood pressure, and neuroendocrinal responses during pediatric cardiac surgery. In a randomized, placebo-controlled study, 30 pediatric patients undergoing open heart surgery were randomly assigned to one of two equal groups. The control group received saline, whereas the treatment group (DEX group) received an initial bolus dose of dexmedetomidine (0.5 microg/kg) over 10 min, followed immediately by a continuous infusion of 0.5 microg.kg(-1).h(-1). Arterial blood pressure, heart rate, and sequential concentrations of circulating cortisol, epinephrine, norepinephrine, and blood glucose were measured. Relative to baseline, arterial blood pressure and heart rate decreased significantly after the administration of dexmedetomidine through skin incision. In the control group, patients' heart rate and arterial blood pressure measures increased after skin incision until the end of bypass (P < 0.05). In both groups, plasma cortisol, epinephrine, norepinephrine, and blood glucose increased significantly relative to baseline, after sternotomy, and after bypass. However, the values were significantly higher in the control group compared with the DEX group (P < 0.05). In 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.