Bertolissi M, De Monte A, Giordano F
Second Department of Anesthesia and Intensive Care Medicine, Azienda Ospedaliera S. Maria della Misericordia, Udine.
Minerva Anestesiol. 1998 Jul-Aug;64(7-8):321-8.
The present study was designed to compare the hemodynamic effects of nifedipine and sodium nitroprusside, intravenously administered to control acute systemic hypertension in the immediate postoperative period after open heart surgery.
The study was carried out on 16 patients who developed acute systemic hypertension, defined as mean systemic arterial pressure (MAP) values above 90 mmHg, within the first hour after ICU admission, which followed cardiac surgery for valvular and coronary disease. After control measurements during the hypertensive status, each patient was treated by alternating infusions of sodium nitroprusside and nifedipine in order to obtain MAP values of about 80 mmHg with each administration. All patients had preoperative left ventricular ejection fraction above 45%.
Nifedipine produced a superior and significant increase in cardiac index (CI) (+28%) and stroke volume index (SVI) (+30%), and a greater decrease in systemic vascular resistance index (SVRI) (-39%), when compared with sodium nitroprusside [CI (+5%), SVI (no change), SVRI (-27%)]. On the contrary the right and left ventricular filling pressures were reduced significantly by sodium nitroprusside [pulmonary capillary wedge pressure (-30%), central venous pressure (-20%)], while nifedipine induced small and not significant changes in the preload values. No ECG changes suggesting ischemic myocardial events were observed in any patient.
On the basis of these results it has been concluded that nifedipine affects primarily the arteriolar resistance vessels without significant changes in venous tone, which is on the contrary markedly reduced by sodium nitroprusside. The better improvement in cardiac index and stroke volume index obtained with the administration of nifedipine, makes this drug a good alternative to sodium nitroprusside for treatment of acute hypertension after cardiac surgery in patients with a good preoperative left ventricular function.
本研究旨在比较静脉注射硝苯地平和硝普钠对心脏直视手术后即刻控制急性全身性高血压的血流动力学影响。
该研究对16例在重症监护病房（ICU）入院后第一小时内发生急性全身性高血压（定义为平均体动脉压（MAP）值高于90 mmHg）的患者进行，这些患者均接受了瓣膜和冠状动脉疾病的心脏手术。在高血压状态下进行对照测量后，每位患者交替输注硝普钠和硝苯地平进行治疗，以使每次给药时MAP值达到约80 mmHg。所有患者术前左心室射血分数均高于45%。
与硝普钠相比，硝苯地平使心脏指数（CI）显著升高（+28%）、每搏量指数（SVI）显著升高（+30%），而全身血管阻力指数（SVRI）显著降低（-39%）[CI（+5%），SVI（无变化），SVRI（-27%）]。相反，硝普钠使右心室和左心室充盈压显著降低[肺毛细血管楔压（-30%），中心静脉压（-20%）]，而硝苯地平对前负荷值的影响较小且无显著变化。所有患者均未观察到提示缺血性心肌事件的心电图变化。
基于这些结果得出结论，硝苯地平主要影响小动脉阻力血管，静脉张力无显著变化，而硝普钠则使静脉张力显著降低。硝苯地平给药后心脏指数和每搏量指数改善更好，使其成为术前左心室功能良好的患者心脏手术后治疗急性高血压时替代硝普钠的良好选择。
