Pontén J, Häggendal J, Milocco I, Waldenström A
Anesth Analg. 1983 Apr;62(4):380-90.
Patients receiving metoprolol before cardiac revascularization surgery were randomly divided into those in whom metoprolol was discontinued before the operation (N = 10) and those in whom metoprolol was continued up to the time of operation (N = 10). Cardiovascular responses to neuroleptanesthesia and sternotomy were studied. Coronary sinus catheterization for blood-flow measurement and sampling was performed in 5 patients in each group. Two of 10 patients had a myocardial infarction after discontinuation of metoprolol and surgery was therefore postponed. Tachycardias were common during intubation after discontinuation of metoprolol, but otherwise hemodynamic responses and myocardial oxygen consumption were similar in both groups. Recurrent ST-T depression occurred in 7 of 8 patients and myocardial lactate release in 2 of 5 patients in whom metoprolol was withdrawn, whereas patients who continued to receive metoprolol showed few episodes of ST-T depression (2 of 10) and no lactate release. The latter had lower plasma norepinephrine (NE) levels, but myocardial release of NE was similar in both groups. Preoperative metoprolol withdrawal seemed to precipitate myocardial ischemia, whereas maintenance of therapy was well tolerated.
在心脏血管重建手术前接受美托洛尔治疗的患者被随机分为两组，一组在手术前停用美托洛尔（N = 10），另一组持续使用美托洛尔直至手术时（N = 10）。研究了对神经安定麻醉和胸骨切开术的心血管反应。每组5例患者进行了冠状窦插管以测量血流量和采样。10例患者中有2例在停用美托洛尔后发生心肌梗死，因此手术推迟。停用美托洛尔后插管期间心动过速很常见，但两组的血流动力学反应和心肌耗氧量相似。停用美托洛尔的8例患者中有7例出现复发性ST-T压低，5例患者中有2例出现心肌乳酸释放，而继续接受美托洛尔治疗的患者很少出现ST-T压低（10例中有2例）且无乳酸释放。后者的血浆去甲肾上腺素（NE）水平较低，但两组心肌NE释放相似。术前停用美托洛尔似乎会引发心肌缺血，而维持治疗耐受性良好。
