Ehrly M
Service de Médecine Interne, Hôpital Universitaire Johann-Wolfgang-Goethe, Frankfurt-am-Main.
Rev Fr Gynecol Obstet. 1991 Feb 25;86(2 Pt 2):131-8.
The oxygen transport chain in mammalians depends on adequate oxygen uptake, oxygen transport and oxygen delivery. In diseases with underlying perfusion disorders, for example chronic occlusive arterial disease, the oxygen uptake by the lungs is not altered and thus the oxygen saturation of arterial blood is normal. In this case however the reduced blood flow does impair the oxygen transport to tissue. Blood flow depends on several factors. In diseases with low flow states, the flow properties of blood play a major role because the viscosity of blood increases in the sense of a vicious circle at low flow rates. Since the hematocrit is one of the determining factors of blood viscosity, one possibility to improve microcirculatory blood flow is to decrease the hematocrit value. The problem is however to reach a hematocrit range whereby the viscosity of blood is markedly improved but without reduction in the oxygen transport capacity. Other methods to increase microcirculatory blood flow at constant hematocrit values are the improvement of red cell deformability and the reduction of erythrocyte aggregation. All these methods are nowadays used in a number of diseases, in which a "hyperviscosity syndrome" is present. In general, an improvement of hemorheological factors like blood and plasma viscosity, erythrocyte deformability and erythrocyte aggregation will improve microcirculatory flow and enhance oxygen supply to tissue.
哺乳动物的氧运输链依赖于充足的氧摄取、氧运输和氧输送。在伴有潜在灌注障碍的疾病中，例如慢性闭塞性动脉疾病，肺的氧摄取未改变，因此动脉血的氧饱和度正常。然而在这种情况下，血流减少确实会损害向组织的氧运输。血流取决于几个因素。在低血流状态的疾病中，血液的流动特性起主要作用，因为在低流速时血液粘度会呈恶性循环增加。由于血细胞比容是血液粘度的决定因素之一，改善微循环血流的一种可能性是降低血细胞比容值。然而问题在于要达到一个血细胞比容范围，在此范围内血液粘度明显改善，但又不降低氧运输能力。在血细胞比容值恒定的情况下增加微循环血流的其他方法是改善红细胞变形性和减少红细胞聚集。如今所有这些方法都用于许多存在“高粘滞综合征”的疾病中。一般来说，改善血液和血浆粘度、红细胞变形性和红细胞聚集等血液流变学因素将改善微循环血流并增强向组织的氧供应。
