Goertz A W, Lass M, Schütz W, Schirmer U, Beyer M, Georgieff M
Department of Anesthesiology, University of Ulm Medical Center, Germany.
J Cardiothorac Vasc Anesth. 1994 Oct;8(5):541-4. doi: 10.1016/1053-0770(94)90166-x.
The effects of calcium gluconate on hemodynamics and saphenous vein graft flow in a group of patients undergoing elective coronary artery bypass grafting who developed ionized hypocalcemia at the end of the surgical procedure were examined. The patients received a central venous bolus of 15 mg/kg of calcium gluconate. Heart rate (HR), arterial pressure (AP), central venous pressure (CVP), pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP), and cardiac output were measured immediately before and 30, 60, 120, 180, and 240 seconds after injection of calcium gluconate. Systemic and pulmonary vascular resistance (SVR and PVR, respectively), cardiac index (CI), stroke volume index (SVI), and right and left ventricular stroke work index (RVSWI and LVSWI, respectively), were calculated. Venous bypass flow velocity (Vbypass-flow) was assessed using a Doppler probe that was attached to the left anterior descending artery (LAD) bypass intraoperatively. Calcium gluconate significantly increased MAP, SVR, and LVSWI from 67 +/- 3 mmHg (mean +/- SEM), 1,128 +/- 128 dyne.s.cm-5 and 25 +/- 3 g.m.beat/m to a maximum of 81 +/- 5 mmHg (P < 0.01), 1,401 +/- 196 dyne.s.cm-5 (P < 0.05), and 32 +/- 4 g.m/beat/m (P < 0.01), respectively. HR, CVP, PAP, PCWP, PVR, CI, SVI, and Vbypass-flow remained unaltered. It is concluded that calcium gluconate administered to moderately hypocalcemic patients increases arterial pressure mainly by peripheral vasoconstriction. Because the increase of arterial pressure, and, thereby, coronary perfusion pressure is not associated with an increase of LAD bypass flow, vasoconstriction in the coronary vascular bed distal to the venous graft cannot be ruled out, and deterioration of the myocardial oxygen supply/demand ratio is strongly suggested.
对一组接受择期冠状动脉搭桥手术且在手术结束时出现离子化低钙血症的患者，研究了葡萄糖酸钙对血流动力学和大隐静脉移植物血流的影响。患者接受了15mg/kg葡萄糖酸钙的中心静脉推注。在注射葡萄糖酸钙前及注射后30、60、120、180和240秒，测量心率（HR）、动脉压（AP）、中心静脉压（CVP）、肺动脉压（PAP）、肺毛细血管楔压（PCWP）和心输出量。计算全身和肺血管阻力（分别为SVR和PVR）、心脏指数（CI）、每搏量指数（SVI）以及右和左心室每搏功指数（分别为RVSWI和LVSWI）。术中使用连接到左前降支动脉（LAD）旁路的多普勒探头评估静脉旁路血流速度（Vbypass-flow）。葡萄糖酸钙使平均动脉压（MAP）、SVR和左心室每搏功指数（LVSWI）从67±3mmHg（平均值±标准误）、1128±128达因·秒·厘米⁻⁵和25±3克·米/次/米显著增加至最高81±5mmHg（P<0.01）、1401±196达因·秒·厘米⁻⁵（P<0.05）和32±4克·米/次/米（P<0.01）。HR、CVP、PAP、PCWP、PVR、CI、SVI和Vbypass-flow保持不变。得出结论，给予中度低钙血症患者葡萄糖酸钙主要通过外周血管收缩增加动脉压。由于动脉压升高，进而冠状动脉灌注压升高与LAD旁路血流增加无关，不能排除静脉移植物远端冠状动脉血管床的血管收缩，强烈提示心肌氧供需比恶化。
