Department of Mechanical Engineering, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, South Korea.
Anal Methods. 2021 Oct 28;13(41):4871-4883. doi: 10.1039/d1ay00948f.
To understand the contributions of rheological properties to microcirculation, the simultaneous measurement of multiple rheological properties under continuous blood flows has been emphasized. However, existing methods exhibit limitations in terms of continuous and simultaneous monitoring. In this study, a simple method is suggested for simultaneously measuring four rheological properties (, red blood cell (RBC) aggregation, blood viscosity, blood junction pressure, and RBC sedimentation) under a continuous blood flow. Using the push-and-back mechanism, which comprises a co-flowing channel, a test chamber, and an air compliance unit (ACU), blood is supplied to the test chamber and restored into the co-flowing channel periodically and reversely. First, RBC aggregation is quantified based on the intensity of the blood image in the test chamber. Second, blood viscosity and blood junction pressure are determined by analyzing the interface in the co-flowing channel. Lastly, RBC sedimentation is evaluated by analyzing the intensity of the blood image in the blood chamber. Based on quantitative studies involving several vital factors, the tubing length of ACU is set to = 30 mm. The reference fluid (glycerin [20%]) is controlled in a periodic on-off manner (period = 240 s, and flow rate = 1 mL h). The blood flow rate is maintained at 1 mL h. Subsequently, the present method is used to determine the rheological properties of several blood samples with different hematocrits or diluents. Compared with previous studies, the present method yields sufficiently consistent trends with respect to the hematocrit level or concentration of dextran solution. The experimental results imply that the present method enables simultaneous and consistent measurements of four rheological properties of blood under continuous blood flows. This method can be regarded as a promising method for monitoring multiple rheological properties of blood circulating under an closed fluidic circuit.
为了理解流变性质对微循环的贡献，已经强调了在连续血流下同时测量多个流变性质。然而，现有的方法在连续和同时监测方面存在局限性。在这项研究中，提出了一种简单的方法，可以在连续血流下同时测量四个流变性质（、红细胞（RBC）聚集、血液粘度、血液连接压力和 RBC 沉降）。使用推挽机制，该机制包括一个共流通道、一个测试室和一个空气顺应单元（ACU），血液周期性和反向地供应到测试室并恢复到共流通道中。首先，基于测试室中血液图像的强度来量化 RBC 聚集。其次，通过分析共流通道中的界面来确定血液粘度和血液连接压力。最后，通过分析血液室中血液图像的强度来评估 RBC 沉降。基于涉及几个重要因素的定量研究，将 ACU 的管长度设置为 = 30mm。参考流体（甘油[20%]）以周期性的开-关方式控制（周期 = 240s，流速 = 1mLh）。血流速度保持在 1mLh。随后，使用该方法确定了具有不同血细胞比容或稀释剂的几种血液样本的流变性质。与以前的研究相比，该方法在血细胞比容水平或右旋糖溶液浓度方面产生了足够一致的趋势。实验结果表明，该方法可以在连续血流下同时测量血液的四个流变性质。该方法可以被视为监测封闭流道中循环血液的多个流变性质的有前途的方法。
