Dexmedetomidine can stabilize hemodynamics and spare anesthetics before cardiopulmonary bypass

Purpose We previously confirmed the effectiveness of dexmedetomidine (DEX) for stabilizing hemodynamics as well as sparing anesthetics during anesthetic induction in patients undergoing cardiac surgery (Kunisawa et al. in J Clin Anesth 21:194–199, 1 ). In this study, we investigated whether these effects of DEX continue until the start of cardiopulmonary bypass (CPB). Methods Twenty-two patients with mild to moderate cardiovascular disease were randomized into two groups [DF2 group: DEX dose of 0.7 μg/kg/h after initial dose and effect-site concentration (ESC) of fentanyl of 2 ng/ml; PF4 group: saline and ESC of fentanyl of 4 ng/ml]. Propofol was administered for anesthetic induction and maintenance. Hemodynamics, cardiovascular drugs, ESC of propofol, and cardiovascular responses to skin incision (SI) and sternotomy (St) were measured or calculated. Results Blood pressure (BP) at the pre-/post-SI periods was higher in the DEX group (137 ± 17/140 ± 16 mmHg) than in the placebo group (85 ± 9/109 ± 24 mmHg). Percent increases in cardiovascular response to SI or St were lower in the DEX group than in the placebo group (for example, 1.9 ± 2.2 vs. 27.4 ± 19.9% in systolic BP due to SI). ESCs of propofol at SI and St in the DEX group were lower than those in the placebo group. Conclusions DEX combined with 2 ng/ml fentanyl before CPB can suppress the decrease in blood pressure at the pre- and post-SI periods, can blunt the cardiovascular responses to SI and St, and can spare the required ESC of propofol despite fentanyl concentration, which was half of that in the placebo group.