定值曲线法测定凝血酶原时间国际标准化比值

Using the Settled Value Curve Method to Detect International Normalized Ratio of Prothrombin Time.

目的:利用正常血浆和定标血浆,建立一种准确可靠、易于实验室开展的凝血酶原时间国际标准化比值检测方法。方法:根据准确度的传递,将被定值的正常血浆和定标血浆同时用称量法分别作6个不相同的稀释度稀释后上机进行检测。将待定值血浆PT值(X轴)与稀释度1/A(Y轴)绘制“校标”曲线;根据定标血浆测得的PT值,用内插法查得相对浓度1/A(X%)与计算相对浓度(Y%)绘制曲线,并进行回归处理得到INR的定值曲线;根据定值曲线绘制PT测(Y轴)与INR测(X轴)INR应用曲线。结果:血浆INR值与PT值有良好的线性关系(r=0.997),同一试剂本方法检测质控血浆INR值,重复性良好(CV<2%);不同试剂测定血浆INR值,结果显示本方法优于公式计算法,其结果与手工结果有很好的相关性(r=0.99),同时比仪器法更接近手工检测法(t检验P值:0.021对0.077)。结论:本方法在检测抗凝治疗患者血浆INR值时,干扰因素少,结果准确可靠,可能更接近待检血浆的INR“真值”。

Objectives： Using normal plasmas and criterion plasmas to establish a kind of accurate and feasible method that could measure international normalized ratio （INR） of prothrombin time （PT）. Methods： According to the delivery of accurate degree, we diluted the settled value normal plasmas and criterion plasmas into six different dilution degrees with weighing method at the same time and measured them with the machine. The criterion curve was made with PT value of the settled value normal plasmas as X axis and the dilution degrees （I/A） as Y axis. According to PT value of standard plasmas, the curve was made with the relative concentration （I/A） as X axis that was acquired from internal insert method and the relative concentration as Y axis that was acquired from calculation. Then, through orthogonal regression, the settled value curve was formed. At last, the applicative curve was made with PT value as X axis and INR value as Y axis according to the settled value curve. Results： INR and PT value of plasmas have good linear relation （ r = O. 997 ）. The repetition of measuring INR value of INR control plasmas in the same regents with this method is good （ CV 〈 2 % ）. The results show that the method is better than formula calculation method when using different regents to measure INR value of plasmas. At the same time, the results from the method and the results from the artificial method have a good relation （ r = 0. 99 ）. They are closer to the resuits from the artificial method than instrument method （t test, P value： 0.021 vs. 0.077）. Conclusions： When the method is used to measure plasmas INR value of patients with anti - coagulation treatment, the interference factor is small, and the result is accurate and reliable. It may be closer to the true value of plasmas.