Institut des Biomolécules Max Mousseron (IBMM) UMR CNRS 5247, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, France.
Laboratoire de Biophysique & Bio-Analyses, Faculté de Pharmacie, Université de Montpellier, France.
Clin Hemorheol Microcirc. 2019;71(4):379-385. doi: 10.3233/CH-199001.
The ideal hematocrit is the hematocrit (Hct) value resulting in the highest value of Hct/viscosity (h/η) ratio and can thus be predicted from viscometric measurements with the use of equations such as Quemada's one which yield the determination of the bell-shaped curve of h/η as a function of Hct. In a series of recent papers we applied this approach to various populations, using viscometry at high shear rate (1000 s-1). However the shape of this curve has been reported to be dependent on the shear rate, resulting in a right-shift in this top value when Hct increase. We present here in 11 young recreative athletes the evolution of the predicted top of the h/η curve and optimal theoretical Hct and the discrepancy between theoretical and optimal values over the range of shear rates 1 to 6000 s-1. Results show that the predicted optimal value of both h/η and Hct increases when shear rate increases and that the discrepancy between predicted laquooptimalraquo and actual values decreases and becomes almost asymptotic at very high shear (500 s-1). It is minimal at 2720 s-1. The correlation between predicted laquooptimalraquo and actual values of both parameters describes the same evolution. Therefore, it is better for assessing h/η and its agreement with theoretical values, and for determining the theoretical ideal hematocrit, to measure blood viscosity at shear rates equal or superior to 500 s-1.
理想的血细胞比容是能产生最高血细胞比容/粘度（h/η）比值的血细胞比容（Hct）值，因此可以通过使用 Quemada 等方程从粘度测量中预测，这些方程可以得出 h/η 作为 Hct 函数的钟形曲线的确定。在最近的一系列论文中，我们将这种方法应用于各种人群，使用高剪切率（1000 s-1）下的粘度计。然而，据报道，这种曲线的形状取决于剪切率，当 Hct 增加时，这个最高值会向右移动。我们在此介绍了 11 名年轻的竞技运动员的 h/η 曲线预测最高值和最佳理论 Hct 的演变，以及在 1 到 6000 s-1 的剪切率范围内理论值和最佳值之间的差异。结果表明，当剪切率增加时，h/η 和 Hct 的预测最佳值都增加，预测“最佳”值与实际值之间的差异减小，并在非常高的剪切（500 s-1）下变得几乎渐近。在 2720 s-1 时最小。这两个参数的预测“最佳”值与实际值之间的相关性描述了相同的演变。因此，在评估 h/η 及其与理论值的一致性，并确定理论理想血细胞比容时，最好在等于或高于 500 s-1 的剪切率下测量血液粘度。
