Department of Anaesthesia, Critical Care and Pain Medicine, Division of General Anaesthesia and Intensive Care Medicine, Medical University of Vienna, Vienna, Austria.
Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria.
Biochem Med (Zagreb). 2022 Jun 15;32(2):020713. doi: 10.11613/BM.2022.020713.
Point-of-care (POC) platelet function tests are faster and easier to perform than in-depth assessment by flow cytometry. At low platelet counts, however, POC tests are prone to assess platelet function incorrectly. Lower limits of platelet count required to obtain valid test results were defined and a testing method to facilitate comparability between different tests was established.
We assessed platelet function in whole blood samples of healthy volunteers at decreasing platelet counts (> 100, 80-100, 50-80, 30-50 and < 30 x10/L) using two POC tests: impedance aggregometry and bleeding time. Flow cytometry served as the gold standard. The number of platelets needed to reach 50% of the maximum function (ED) and the lower reference limit (ED) were calculated to define limits of test validity.
The minimal platelet count required for reliable test results was 100 x10/L for impedance aggregometry and bleeding time but only 30 x10/L for flow cytometry. Comparison of ED and ED showed significantly lower values for flow cytometry than either POC test (P value < 0.05) but no difference between POC tests nor between the used platelet agonists within a test method.
Calculating the ED and ED provides an effective way to compare values from different platelet function assays. Flow cytometry enables correct platelet function testing as long as platelet count is > 30 x10/L whereas impedance aggregometry and bleeding time are inconsistent unless platelet count is > 100 x10/L.
即时检验（POC）血小板功能检测比流式细胞仪的深入评估更快、更容易。然而，在血小板计数较低的情况下，POC 检测容易错误地评估血小板功能。为了获得有效的检测结果，定义了所需的最低血小板计数下限，并建立了一种有助于不同检测之间可比性的检测方法。
我们使用两种 POC 检测方法（阻抗聚集法和出血时间）评估了健康志愿者在血小板计数逐渐降低（> 100、80-100、50-80、30-50 和 < 30 x10/L）的全血样本中的血小板功能。流式细胞术作为金标准。计算达到最大功能 50%所需的血小板数量（ED）和下限参考值（ED），以定义检测有效性的限制。
阻抗聚集法和出血时间可靠检测结果所需的最低血小板计数为 100 x10/L，但流式细胞术仅需 30 x10/L。ED 和 ED 的比较显示，流式细胞术的数值明显低于任何一种 POC 检测（P 值<0.05），但 POC 检测之间以及同一检测方法内使用的血小板激动剂之间没有差异。
计算 ED 和 ED 为比较来自不同血小板功能检测的数值提供了一种有效的方法。只要血小板计数>30 x10/L，流式细胞术就能正确进行血小板功能检测，而阻抗聚集法和出血时间则不一致，除非血小板计数>100 x10/L。
