Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium.
Department of Mathematics, Namur Institute for Complex System (naXys), University of Namur, Namur, Belgium.
Int J Lab Hematol. 2019 Jun;41(3):316-324. doi: 10.1111/ijlh.12975. Epub 2019 Feb 7.
Clot waveform analysis (CWA), a new methodology to assess coagulation process, can be usefully applied in various clinical settings. However, its clinical use is limited mainly because of the absence of standardization. No consensus exists regarding the wavelengths at which CWA has to be performed what is crucial for the sensitivity of the CWA.
The primary aim of this study is to determine which wavelength is the most sensitive and specific for CWA. Interindividual baseline absorbance will also be assessed as the impact of reagents from the intrinsic, extrinsic, and common coagulation pathway will be determined.
Plasma samples were screened at wavelengths from 280 to 700 nm to provide absorbance spectra in clotted and nonclotted plasma. The interindividual variability of baseline absorbance was obtained by screening plasma from 50 healthy individuals at 340, 635, and 671 nm. The inner-filter effect of reagents was assessed in plasma or serum when appropriate at the same wavelengths. The reagents were those commonly used for activated partial thromboplastin time, prothrombin time, thrombin time, and dilute Russell's viper venom time.
Clotted plasma has higher absorbance value than nonclotted plasma (P < 0.01). The absorbance of all type of samples is higher at 340 nm than at >600 nm (P < 0.01). The interindividual variability at the different wavelengths was around 25%. However, except with the STA®-CKPrest® and STA®-NeoPTimal®, the reagents do not have a significant effect on the baseline absorbance.
Wavelengths above 650 nm are recommended to perform CWA. Most of the commercialized reagents can be used for CWA.
血栓波形分析（CWA）是一种评估凝血过程的新方法，可在各种临床环境中得到有效应用。然而，其临床应用受到限制，主要是因为缺乏标准化。关于 CWA 必须进行的波长以及这对 CWA 的灵敏度至关重要的波长，尚未达成共识。
本研究的主要目的是确定 CWA 最敏感和最特异的波长。还将评估个体间基线吸光度，因为将确定内在、外在和共同凝血途径的试剂的影响。
在 280 至 700nm 的波长下筛选血浆样本，以提供在凝结和未凝结血浆中的吸光度光谱。通过在 340、635 和 671nm 处筛选来自 50 名健康个体的血浆来获得个体间基线吸光度的可变性。在适当的情况下，在相同波长下评估试剂在血浆或血清中的内滤光效应。所用的试剂为通常用于活化部分凝血活酶时间、凝血酶原时间、凝血酶时间和稀释的 Russell 蝰蛇毒时间的试剂。
凝结的血浆比未凝结的血浆具有更高的吸光度值（P<0.01）。所有类型的样本在 340nm 的吸光度均高于>600nm（P<0.01）。在不同波长下的个体间可变性约为 25%。但是，除 STA®-CKPrest®和 STA®-NeoPTimal®外，试剂对基线吸光度没有显著影响。
建议使用 650nm 以上的波长进行 CWA。大多数商业化的试剂可用于 CWA。
