Wise R A, Malamet R, Wigley F M
J Rheumatol. 1987 Apr;14(2):278-83.
In order to determine the acute effect of nifedipine, a calcium channel blocker, on digital hemodynamics in patients with Raynaud's phenomenon, we studied 21 patients in a double blinded, placebo controlled trial. Digital blood flow at room temperature was measured by venous occlusion plethysmography as perfusion pressures were lowered by elevating the hand above the level of the heart. After placebo, there was a small reduction in digital blood flow without any alteration in the perfusion pressure. After nifedipine, there was a significant reduction in both perfusion pressure and digital blood flow at each level of hand elevation. When analyzed as pressure-flow relationships, there was no significant change after nifedipine, indicating that the fall in blood flow could be accounted for by the reduction in perfusion pressure. Four of the placebo group developed Raynaud's phenomenon after the baseline study, whereas none developed Raynaud's phenomenon after nifedipine. Our results suggest that although nifedipine may reduce vascular reactivity, caution is warranted in use of this drug in patients with threatened digital ischemia because of the possibility that digital blood flow may be reduced.
为了确定钙通道阻滞剂硝苯地平对雷诺现象患者手指血流动力学的急性影响，我们在一项双盲、安慰剂对照试验中研究了21例患者。通过静脉阻断体积描记法测量室温下的手指血流量，同时将手举过心脏水平以降低灌注压。服用安慰剂后，手指血流量略有减少，而灌注压无任何改变。服用硝苯地平后，在每个手举高度水平，灌注压和手指血流量均显著降低。当分析压力-流量关系时，服用硝苯地平后无显著变化，这表明血流量的下降可归因于灌注压的降低。安慰剂组中有4例患者在基线研究后出现雷诺现象，而服用硝苯地平后无患者出现雷诺现象。我们的结果表明，尽管硝苯地平可能会降低血管反应性，但由于可能会减少手指血流量，因此在有手指缺血风险的患者中使用该药时应谨慎。
