Malan T P, DiNardo J A, Isner R J, Frink E J, Goldberg M, Fenster P E, Brown E A, Depa R, Hammond L C, Mata H
Department of Anesthesiology, University of Arizona Health Sciences Center, Tucson 85724, USA.
Anesthesiology. 1995 Nov;83(5):918-28. doi: 10.1097/00000542-199511000-00004.
Sevoflurane is a new inhalational anesthetic with desirable clinical properties. In some clinical situations, an understanding of the detailed cardiovascular properties of an anesthetic is important, so the authors evaluated the hemodynamic effects of sevoflurane in healthy volunteers not undergoing surgery.
Twenty-one subjects were randomized to receive sevoflurane, isoflurane, or sevoflurane: 60% N2O. Anesthesia was induced and maintained by inhalation of the designated anesthetic. Hemodynamic measurements were performed before anesthesia, during controlled ventilation, during spontaneous ventilation, and again during controlled ventilation after 5.5 h of anesthesia.
A few subjects became excessively hypotensive at high anesthetic concentrations (2.0 minimum alveolar concentration [MAC] sevoflurane, 1.5 and 2.0 MAC isoflurane), preventing data collection. Sevoflurane did not alter heart rate, but decreased mean arterial pressure and mean pulmonary artery pressure. Cardiac index decreased at 1.0 and 1.5 MAC, but in subjects with mean arterial pressure > or = 50 mmHg returned to baseline values at 2.0 MAC when systemic vascular resistance decreased. Sevoflurane did not alter echocardiographic indices of ventricular function, but did decrease an index of afterload. Sevoflurane caused a greater decrease in mean pulmonary artery pressure than did isoflurane, but the cardiovascular effects were otherwise similar. Administration of sevoflurane with 60% N2O, prolonged administration or spontaneous ventilation resulted in diminished cardiovascular depression.
At 1.0 and 1.5 MAC, sevoflurane was well tolerated by healthy volunteers. At 2.0 MAC, in subjects with mean arterial pressure > or = 50 mmHg, no adverse cardiovascular properties were noted. Similar to other contemporary anesthetics, sevoflurane caused evidence of myocardial depression. Hemodynamic instability was noted in some subjects at high anesthetic concentrations in the absence of surgical stimulation. The incidence was similar to that with isoflurane. The cardiovascular effects of sevoflurane were similar to those of isoflurane, an anesthetic commonly used in clinical practice since 1981.
七氟醚是一种具有良好临床特性的新型吸入麻醉剂。在某些临床情况下，了解麻醉剂详细的心血管特性很重要，因此作者评估了七氟醚对非手术健康志愿者的血流动力学影响。
21名受试者被随机分为接受七氟醚、异氟醚或七氟醚：60%氧化亚氮。通过吸入指定麻醉剂诱导并维持麻醉。在麻醉前、控制通气期间、自主通气期间以及麻醉5.5小时后再次进行控制通气期间进行血流动力学测量。
少数受试者在高麻醉浓度（2.0最低肺泡浓度[MAC]七氟醚、1.5和2.0 MAC异氟醚）时出现过度低血压，导致无法收集数据。七氟醚不改变心率，但降低平均动脉压和平均肺动脉压。心脏指数在1.0和1.5 MAC时降低，但在平均动脉压≥50 mmHg的受试者中，当体循环血管阻力降低时，在2.0 MAC时恢复到基线值。七氟醚不改变心室功能的超声心动图指标，但确实降低了后负荷指标。七氟醚比异氟醚导致平均肺动脉压下降幅度更大，但心血管效应在其他方面相似。七氟醚与60%氧化亚氮合用、延长给药时间或自主通气导致心血管抑制减轻。
在1.0和1.5 MAC时，健康志愿者对七氟醚耐受性良好。在2.0 MAC时，平均动脉压≥50 mmHg的受试者未观察到不良心血管特性。与其他当代麻醉剂相似，七氟醚导致心肌抑制的证据。在没有手术刺激的高麻醉浓度下，一些受试者出现血流动力学不稳定。发生率与异氟醚相似。七氟醚的心血管效应与异氟醚相似，异氟醚自1981年以来一直在临床实践中常用。
