儿童低温体外循环围术期内皮细胞凝血及纤溶活性变化

Coagulation and fibrinolysis function changes of endothelial cells in pediatric cardiac operation with hypothermic cardiopulmonary bypass

目的 探讨儿童低温体外循环围术期内皮细胞凝血及纤溶活性变化。方法 选择 2 0例先天性心脏病缺损患儿 ,于肝素化后体外循环前、转流 3 0min、开放主动脉 5min、停机、停机后 4h、术后第 1日晨取静脉血测循环内皮细胞 (CEC)数 ,同时用酶联免疫法测定血浆中血管性假血友病因子 (vWF)浓度、组织型纤溶酶原激活剂 (t PA)及纤溶酶原激活剂抑制物 1(PAI 1)活性 ,并测定血不同时间的CEC数。结果 体外循环期间及体外循环结束后各时相点CEC数、vWF浓度均较体外循环前显著增加 (P <0 0 5 ) ;体外循环期间t PA活性显著升高 (P <0 0 5 ) ,停机后t PA活性逐渐下降 ,术后第 1日t PA活性与转流前无显著差别 (P >0 0 5 ) ;转流后PAI 1活性显著下降 (P <0 0 5 ) ,停机后PAI 1活性显著升高 (P <0 0 5 )。结论 低温体外循环可致血管内皮细胞激活或损伤 。

Objective To investigate endothelial cells coagulation and fibrinolytic function changes in pediatric cardiac operation with hypothermic cardiopulmonary bypass (CPB). Methods Twenty children scheduled for cardiac operation with hypothermic CPB were included in the study. Blood samples were taken before CPB, 30 min after the start of CPB, 5 min after release of aortic crossclamp, at the end of CPB, 4 h after the end of CPB and on the morning of first postoperative day. von Willebrand Factor(vWF), tissue type plasminogen activator(t PA) and plasminogen activator inhibitor 1(PAI 1) activity were measured by enzyme linked immunosorbent assay method. Circulating endothelial cells (CEC) were counted. Results The level of CEC and vWF increased significantly during CPB and was remained higher than the basic values on the morning of the first postoperative day ( P <0.05). t PA activity rose significantly throughout CPB( P <0.05) and returned to the baseline in the first postoperation day. PAI 1 activity fell during CPB and increased significantly postbypass( P <0.05). Conclusion Endothelial cells are activated/injured during CPB with hypothermia and interferes blood coagulation and fibrinolysis function.