검체의 보관방법과 시간 및 온도가 PT, aPTT 검사에 미치는 영향

Abstract

We studied the stability of prothrombin time(PT) and activated partial thromboplastin time (aPTT) in 23 samples of healthy volunteers under different storage conditions. For this study, each blood sample was grouped into plasma and whole blood. πle temperatures for storage of the plasma were at room temperature, at 4 degrees C and at -20 degrees C and the times for storage were from 0 hour up to 48hrs(at 0 , 4, 8, 16, 24 and 48 hours). Thewhole blood was analysed under the same storage conditions as plasma except frozen storage condition. We defined that PT and aPTT were clinically stable if the percent(%) value of change was within 5 %. our data demonstrated that PT results of plasma was stable for up to 24hrs regardless of storage temperature and at both 4 degrees C and -20 degrees C stable for up to 48 hrs. PT results of whole blood was stable for up to 24 hrs at room temperature while at 4 degrees C the stability was less than 4hrs. on the other hand, aPTT of plasma was stable for up to 8 hrs either at room temperature or at 4 degrees C while for up to 48 hrs stable in freezing condition. Interestingly, We obserbed that aPTT stabililty of wholeblood was no more than 4 hrs. From this study, it was found that the PT test was not easily affected by the temperature, storage time and the form of storage in comparison with the APTT test which was much easily affected by the above conditions. APTT should be done within 8 hoursafter blood was centrifuged immediately and the plasma should be stored freezing in order to obtain a reliable result.