Talke P, Li J, Jain U, Leung J, Drasner K, Hollenberg M, Mangano D T
Department of Anesthesia, University of California, San Francisco 94143-0648.
Anesthesiology. 1995 Mar;82(3):620-33. doi: 10.1097/00000542-199503000-00003.
Dexmedetomidine, a highly selective alpha 2-adrenergic agonist, increases perioperative hemodynamic stability in healthy patients but decreases blood pressure and heart rate. The goal of this study was to evaluate, in a preliminary manner, the hemodynamic effects of perioperatively administered dexmedetomidine in surgical patients at high risk for coronary artery disease.
Twenty-four vascular surgery patients received a continuous infusion of placebo or one of three doses of dexmedetomidine, targeting plasma concentrations of 0.15 ng/ml (low dose), 0.30 ng/ml (medium dose), or 0.45 ng/ml (high dose) from 1 h before induction of anesthesia until 48 h postoperatively. All patients received standardized anesthesia and hemodynamic management. Blood pressure, heart rate, and Holter ECG were monitored; additional monitoring included continuous 12-lead ECG preoperatively, anesthetic concentrations and myocardial wall motion (echocardiography) intraoperatively, and cardiac enzymes postoperatively.
Preoperatively, there was a decrease in heart rate (low dose 11%, medium dose 5%, high dose 20%) and systolic blood pressure (low dose 3%, medium dose 12%, high dose 20%) in patients receiving dexmedetomidine. Intraoperatively, dexmedetomidine groups required more vasoactive medications to maintain hemodynamics within predetermined limits. Postoperatively, demedetomidine groups had less tachycardia (minutes/monitored hours) than the placebo group (placebo 23 min/h; low dose 9 min/h, P = 0.006; medium dose 0.5 min/h, P = 0.004; high dose 2.3 min/h, P = 0.004). Bradycardia was rare in all groups. There were no myocardial infarctions or discernible trends in the laboratory results.
Infusion of dexmedetomidine up to a targeted plasma concentration of 0.45 ng/ml appears to benefit perioperative hemodynamic management of surgical patients undergoing vascular surgery but required greater intraoperative pharmacologic intervention to support blood pressure and heart rate.
右美托咪定是一种高选择性α2肾上腺素能激动剂，可提高健康患者围手术期的血流动力学稳定性，但会降低血压和心率。本研究的目的是初步评估围手术期给予右美托咪定对冠状动脉疾病高危手术患者的血流动力学影响。
24例血管外科手术患者接受持续输注安慰剂或三种剂量右美托咪定之一，从麻醉诱导前1小时至术后48小时，目标血浆浓度分别为0.15 ng/ml（低剂量）、0.30 ng/ml（中剂量）或0.45 ng/ml（高剂量）。所有患者均接受标准化麻醉和血流动力学管理。监测血压、心率和动态心电图；额外监测包括术前连续12导联心电图、术中麻醉浓度和心肌壁运动（超声心动图）以及术后心肌酶。
术前，接受右美托咪定的患者心率（低剂量组降低11%，中剂量组降低5%，高剂量组降低20%）和收缩压（低剂量组降低3%，中剂量组降低12%，高剂量组降低20%）有所下降。术中，右美托咪定组需要更多血管活性药物以将血流动力学维持在预定范围内。术后，右美托咪定组的心动过速（每分钟/监测小时数）少于安慰剂组（安慰剂组23分钟/小时；低剂量组9分钟/小时，P = 0.006；中剂量组0.5分钟/小时，P = 0.004；高剂量组2.3分钟/小时，P =
