Paris A, Scholz J, von Knobelsdorff G, Tonner P H, Schulte am Esch J
Department of Anesthesiology, University Hospital Eppendorf, Hamburg, Germany.
Anesth Analg. 1998 Sep;87(3):569-73. doi: 10.1097/00000539-199809000-00013.
In the present study, we investigated the effect of remifentanil on cerebral blood flow velocity (CBFV). We investigated 20 patients (ASA physical status III) scheduled for elective coronary artery bypass graft surgery. Anesthesia was induced with remifentanil 5 microg/kg IV (Group 1, n = 10) or 2 microg/kg IV (Group 2, n = 10) and was maintained with 3 microg x kg(-1) x min(-1) IV (Group 1) or 1 microg x kg(-1) x min (-1) IV (Group 2). Pancuronium (0.1 mg/kg IV) was administered for muscle relaxation. Assisted ventilation followed by controlled ventilation via a mask was performed with the PaCO2 kept constant. Mean cerebral blood flow velocity (Vmean) was measured in the middle cerebral artery using a transcranial Doppler sonography system. Mean arterial pressure (MAP) was kept constant by the IV administration of norepinephrine. Measurements were made at baseline and every minute after remifentanil infusion for 10 min. Data were analyzed by using analysis of variance and a post hoc t-test (P < 0.05). Heart rate, MAP, and PaCO2 did not change over time in either group. Vmean did not change in Group 2. In contrast, there was a 31% decrease of Vmean in Group 1 (P < 0.05). The results show that large-dose, but not moderate-dose, remifentanil reduces CBFV unrelated to any changes in systemic hemodynamics in isocapnic cardiac patients.
Transcranial Doppler sonography was used to monitor remifentanil-induced changes in cerebral perfusion. We found that large doses of remifentanil reduced cerebral blood flow velocity despite constant perfusion pressure. This may implicate a central mechanism for cerebral hemodynamic effects of remifentanil.
在本研究中，我们调查了瑞芬太尼对脑血流速度（CBFV）的影响。我们研究了20例计划进行择期冠状动脉搭桥手术的患者（ASA身体状况Ⅲ级）。一组（n = 10）静脉注射5μg/kg瑞芬太尼诱导麻醉，另一组（n = 10）静脉注射2μg/kg瑞芬太尼诱导麻醉，随后分别以3μg·kg⁻¹·min⁻¹（第一组）和1μg·kg⁻¹·min⁻¹（第二组）静脉维持麻醉。静脉注射泮库溴铵（0.1mg/kg）用于肌肉松弛。通过面罩进行辅助通气，随后进行控制通气，使PaCO₂保持恒定。使用经颅多普勒超声系统测量大脑中动脉的平均脑血流速度（Vmean）。通过静脉注射去甲肾上腺素使平均动脉压（MAP）保持恒定。在基线时以及瑞芬太尼输注10分钟后每分钟进行测量。数据采用方差分析和事后t检验进行分析（P < 0.05）。两组患者的心率、MAP和PaCO₂均未随时间变化。第二组的Vmean没有变化。相比之下，第一组的Vmean下降了31%（P < 0.05）。结果表明，在等碳酸血症的心脏患者中，大剂量而非中等剂量的瑞芬太尼会降低CBFV，且与全身血流动力学的任何变化无关。
经颅多普勒超声用于监测瑞芬太尼引起的脑灌注变化。我们发现，尽管灌注压力恒定，但大剂量瑞芬太尼仍会降低脑血流速度。这可能意味着瑞芬太尼对脑血流动力学影响存在中枢机制。
