Hohner P, Backman C, Diamond G, Friedman A, Häggmark S, Johansson G, Karp K, Reiz S
Department of Anesthesiology, University of Umeå, Sweden.
Acta Anaesthesiol Scand. 1994 Nov;38(8):793-804. doi: 10.1111/j.1399-6576.1994.tb04007.x.
This study examines the effects of nitrous oxide on haemodynamics, anterior left ventricular (LV) function and incidence of myocardial ischaemia in abdominal vascular surgical patients with coronary artery disease. Forty-seven patients were randomly assigned to isoflurane-fentanyl anaesthesia with nitrous oxide-oxygen vs air-oxygen (control). Systemic and coronary haemodynamics, 12-lead ECG, LV anterior wall motion by cardiokymography (CKG) and myocardial lactate balance were recorded at four intervals: before and during anaesthesia and 10 and 30 minutes into surgery. Systemic haemodynamics were controlled by anaesthetic dose, and, when insufficient, by i.v. nitroglycerine (NG) in case of LV failure (PCWP > 18 mmHg) and by phenylephrine during hypotension. We found that nitrous oxide was associated with greater need for i.v. nitroglycerin (patients: P = 0.031, episodes P = 0.005) and more myocardial ischaemia (patients P = 0.012, episodes P = 0.001) despite systemic and coronary haemodynamics comparable to the control group. We conclude that nitrous oxide, known to have both sympathomimetic and cardiodepressive actions, produced cardiodepression in the face of sympathetic stimulation. Our study design did not allow to conclude if myocardial ischaemia was the consequence of increased wall stress or a reason for the observed LV dysfunction. The higher incidence of introperative myocardial ischaemia and need for NG did not cause increased cardiac morbidity.
本研究探讨氧化亚氮对患有冠状动脉疾病的腹部血管外科手术患者的血流动力学、左心室前壁功能及心肌缺血发生率的影响。47例患者被随机分配接受异氟烷-芬太尼麻醉并吸入氧化亚氮-氧气或空气-氧气（对照组）。在四个时间点记录全身和冠状动脉血流动力学、12导联心电图、通过心动记波法（CKG）测量的左心室前壁运动以及心肌乳酸平衡：麻醉前、麻醉期间、手术开始后10分钟和30分钟。全身血流动力学通过麻醉剂量控制，不足时，左心室衰竭（肺毛细血管楔压>18 mmHg）时静脉注射硝酸甘油（NG），低血压时使用去氧肾上腺素。我们发现，尽管全身和冠状动脉血流动力学与对照组相当，但氧化亚氮与更多静脉注射硝酸甘油的需求相关（患者：P = 0.031，发作次数：P = 0.005）以及更多的心肌缺血（患者：P = 0.012，发作次数：P = 0.001）。我们得出结论，已知具有拟交感神经和心脏抑制作用的氧化亚氮，在交感神经刺激的情况下产生了心脏抑制作用。我们的研究设计无法得出心肌缺血是壁应力增加的结果还是观察到的左心室功能障碍的原因。术中心肌缺血的较高发生率和对硝酸甘油的需求并未导致心脏发病率增加。
