Lawrence Matthew J, Kumar Sendhil, Hawkins Karl, Boden Stuart, Rutt Harvey, Mills Gavin, Sabra Ahmed, Morris Roger H K, Davidson Simon J, Badiei Nafieseh, Brown Martin R, Williams Phylip R, Evans Phillip A
NISCHR Haemostasis Biomedical Research Unit, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK; NISCHR Haemostasis Biomedical Research Unit, College of Medicine, Swansea University, Swansea, UK.
Emergency Department, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK.
Thromb Res. 2014 Aug;134(2):488-94. doi: 10.1016/j.thromres.2014.05.039. Epub 2014 Jun 6.
We investigated the effect of progressive haemodilution on the dynamics of fibrin clot formation and clot microstructure using a novel rheological method. The technique measures clotting time (TGP), clot strength (G`GP), and quantifies clot microstructure (df) at the incipient stages of fibrin formation. We use computational modelling to examine the relationship between structure and mass, as well as helium ion microscopy (HIM) to compare morphological changes in the fully formed clot to that of the incipient clot.
This is an in vitro study; 90 healthy volunteers were recruited with informed consent and a 20ml sample of whole blood obtained from each volunteer. Five clinically relevant dilutions were investigated using 0.9w.v isotonic saline (0, 10, 20, 40 and 60%, n=18 for each dilution). The rheological method of assessing structural clot changes was compared against conventional coagulation screen and fibrinogen estimation.
Fractal dimension (df) and final clot microstructure both decreased with progressive dilution (significant at a dilution of 20%) with similar relationships observed for final clot characteristics in HIM images. Significant correlations were observed between df and G`GP (clot strength) (0.345, p=0.02), as well as clotting time (PT: -0.690, p>0.001; APTT: -0.672, p>0.001; TGP: -0.385, p=0.006).
This study provides new insight into the effects of haemodilution by isotonic saline on clotting time (TGP), clot strength (G'GP) and clot microstructure (df). Previous studies have attempted to link clot microstructure to clot quality/strength, however this study provides a significant step in quantifying these relationships.
我们使用一种新型流变学方法研究了渐进性血液稀释对纤维蛋白凝块形成动力学和凝块微观结构的影响。该技术可测量凝血时间（TGP）、凝块强度（G`GP），并在纤维蛋白形成的初始阶段对凝块微观结构进行量化（df）。我们使用计算模型来研究结构与质量之间的关系，并使用氦离子显微镜（HIM）来比较完全形成的凝块与初始凝块的形态变化。
这是一项体外研究；招募了90名健康志愿者并获得知情同意，从每位志愿者身上采集20ml全血样本。使用0.9w.v等渗盐水研究了五种临床相关的稀释度（0、10、20、40和60%，每种稀释度n = 18）。将评估凝块结构变化的流变学方法与传统凝血筛查和纤维蛋白原估计进行了比较。
随着稀释度的增加，分形维数（df）和最终凝块微观结构均降低（在20%稀释度时显著），HIM图像中最终凝块特征呈现相似关系。观察到df与G`GP（凝块强度）之间存在显著相关性（0.345，p = 0.02），以及与凝血时间之间存在显著相关性（PT：-0.690，p>0.001；APTT：-0.672，p>0.001；TGP：-0.385，p = 0.006）。
本研究为等渗盐水血液稀释对凝血时间（TGP）、凝块强度（G'GP）和凝块微观结构（df）的影响提供了新的见解。以往的研究试图将凝块微观结构与凝块质量/强度联系起来，然而本研究在量化这些关系方面迈出了重要一步。
