血小板凝血活性对预防性血小板输注的预示价值研究

Predictive values of hemostatic activity of platelet on prophylactic transfusion

目的探讨血小板凝血活性对预防性血小板输注的预示价值并确定血小板预防性输注的界值。方法采用活化血浆凝固时间(APCT)和血栓弹力图(TEG)检测血小板凝血活性。根据病人有无出血表现,将127例血小板计数(PLT)<50×109/L的患者分为两组,其中出血组37例,未出血组90例。抽取4.5ml静脉血,枸橼酸钠抗凝,进行PLT、TEG、APCT测定。结果出血组和未出血组的PLT和APCT分别为(7.9±3.6)×109/L、104.0±6.1s和(23.0±10.1)×109/L、68.4±9.4s,两者均有显著差异,P<0.01;PLT和APCT呈负相关,r=-0.7613。出血组病人(n=15)TEG的MA参数值(TEG-MA)为20.5±5.3mm,低于未出血组病人(n=20)的43.4±11.0mm,有显著差异,P<0.01。以APCT≥90s为界值,其预示血小板减少所致出血的敏感性为100%,特异性为98.9%;以MA≤30mm为界值,预示敏感性为100%,特异性为95.0%;以PLT≤20×109/L为界值,敏感性为100%,特异性为56.7%。结论血小板凝血活性是预示血小板减少所致出血的良好指标,其特异性明显优于PLT。以APCT≥90s或TEG-MA≤30mm作为血小板输注的界值可有效地预防由血小板减低引起的出血。

Objective To investigate the predictive values of hemostatic activity of platelets on prophylactic transfusion, and determine the threshold of prophylactic platelet transfusion to avoid the bleeding risk caused by thrombocytopenia. Methods One hundred and twenty-seven patients whose platelet count （Pit） 〈 50 ×10^9/L were divided into 2 groups：37 with bleeding symptoms （bleeding group） and 90 without bleeding symptoms （ non-bleeding group）. 4.5 ml of venous blood was collected into the tube with 0.5 ml 3.2% sodium citrate. The platelets hemostatic activity was evaluated by activated plasma clotting time （APCT） and thrombelastography （TEG）. Results Pit and APCT in the bleeding group were （ 7.9 _± 3.6 ） ×10^9/L and 104.0 ± 6.1 s, and in the non-bleeding group were （23,0 ± 10.1 ） ×10^9/L and 68.4 ± 9.4s, respectively. There were statistically significant differences for the both parameters between the two groups（ P 〈 0.01 ）. The APCT was negatively correlated with Pit （ r = - 0. 7613 ）. The TEG maximum amplitude （ TEG-MA ） were 20.5 ± 5.3 mm in the bleeding group （ n = 15 ） and 43.4 ± 11.0 mm in the non-bleeding group （ n = 20 ） （ P 〈 0.01 ）. When APCT ≥90 s was used as the cut-off point to predict the bleeding risk caused by thrombocytopenia, the sensibility and specificity were 100% and 98.9%. When TEG-MA≤ 30 mm was used as the cut-off point, the sensibility and specificity were 100% and 95.0%. When Pit ≤20 ×10^9/L was used as the cut-off point, the sensibility and specificity were 100% and 56.7%. Conclusions The specificity of APCT or TEG-MA for predicting bleeding risk caused by thrombocytopenia was evidently superior to Plt. APCT ≥ 90s or TEG-MA ≤30mm as the cutoff value for prophylactic platelet transfusion may effectively prevent bleeding due to thrombocytopenia.