实验前相关因素对测定新生儿血浆PT、APTT的影响

目的探讨抗凝、离心、黄疸等实验前相关因素对测定新生儿血浆凝血酶原时间（PT）、活化部分凝血活酶时间（API]r）的影响，从而进一步优化试验条件。方法本试验选取100名外科术前体检无异常发现的新生儿，所有入选新生儿均无血栓性疾病及出凝血功能障碍，无心、肾、肝等重要脏器疾病。将此100名新生儿分为3组，分别为抗凝剂比例影响组（包括抗凝剂比例9：1组和抗凝剂比例校正组）、离心条件影响组[2000r／min（离心半径为10cm）离心10min；3000r／min（离心半径为10em）离心10min组；2500r／min（离心半径为10cm）离心15min组]、生理性黄疸影响组。利用STAGO全自动血凝分析仪对以上几个处理组的标本进行检测，并且使用SPSS13．0统计软件对得到的数据进行比较，从而逐步优化实验条件。结果在相同离心条件下，抗凝剂9：1组的PT、APlTr明显延长。在抗凝剂比例经过校正的情况下，2000r／min（离心半径为10em）离心10min组的PT、APTT明显延长；3000r／min（离心半径为10cm）离心10min组中大部分标本PT、APTT正常，个别出现溶血的标本PT明显延长。2500r／min（离心半径为10cm）离心15min是新生儿检测胛、APTT的最适离心条件。在抗凝剂比例经过校正，2500r／min（离心半径为10cm）离心15min的条件下，生理性黄疸组与无生理性黄疸组的胛、APTT比较差异无统计学意义。结论在处理新生儿血浆标本时，应进行抗凝剂比例校正，离心转速不宜过快，否则容易引起溶血，从而引起实验误差。可以通过适当降低离心速度，延长离心时间来避免这种情况的发生。生理性黄疸基本不影响PT、APTT的测定。

The influence factors of anticoagulant, centrifugation and icterus on the test of plasma prothrombin time and activated partial thromboplastin time in newborns

Objective To study the influence of anticoagulant,centrifugation and icterus on the tests of plasma prothrombin time (PT) and activated partial thromboplastin time (APTT) in newborns and further optimize the experimental conditions of PT and APTT. Methods 100 healthy newborns without thrombotic disease, disorder of blood clotting, cardiac disease, renal disease and liver disease were selected and divided into 3 groups (influence factor of anticoagulant, influence factor of centrifugation and influence factor of physiologic icterus). The group influence factor of anticoagulant included 2 groups (the anticoagulant ratio of 9∶ 1 group and the anticoagulant ratio of correction group). The group influence factor of centrifugation included 3 groups (2 000 r/min (centrifugal radius=10 cm) 10 min group; 3 000 r/min (centrifugal radius=10 cm) 10 min group and 2 500 r/min (centrifugal radius=10 cm) 15 min group). The samples were detected by STAGO automatic blood coagulation analyzer. The results were compared by SPSS 13.0. The conditions were optimized step by step. Results PT and APTT in the anticoagulant ratio of 9∶ 1 group were obviously longer than those in the anticoagulant ratio of correction group under the same centrifugation condition. PT and APTT in the group of 2 000 r/min (centrifugal radius=10 cm) 10 min were obviously longer than those in the other groups. Most results in the group of 3 000 r/min (centrifugal radius=10 cm) 10 min were normal, but the results of PT in some haemolytic samples were obviously longer. The optimum condition for centrifugation was 2 500 r/min (centrifugal radius=10 cm) 15 min in the tests of PT and APTT. There was no significant difference of PT and APTT between the groups of physiologic icterus and no physiologic icterus. Conclusions It is very important to correct the volume of anticoagulant for the plasma samples of the newborns. If the speed of centrifugation is too fast, the samples are easy to hemolysis. The haemolytic samples can interfere the results of PT and APTT. The problem can be solved by reducing the speed and extending the time of centrifugation. The physiologic icterus samples do not interfere the results of PT and APTT.