体外循环下P-选择素与D-二聚体变化的临床研究

目的探讨体外循环对血小板活化及血管内皮细胞损伤的影响及其相互之间的关系。方法对21例风湿性心脏病患者在体外循环前、中、后等5个时点采血，用流式细胞仪检测血小板膜P选择素的表达率及荧光强度，同时用ELISA检测血浆中P选择素及D-二聚体的含量。结果血小板膜P选择素的表达率从体外循环中15min开始上升，60min时达高峰，之后逐渐下降，术后24h仍高于术前水平，各时点之间的差异具统计学意义（P〈0．01）。血浆P选择素和D-二聚体浓度的变化规律与血小板膜P选择素阳性率基本类似，三者之间Pearson相关系数均〉0．85（P〈0．01），呈明显的正相关。P选择素的荧光强度变化不明显（P〉0．05）。结论随着体外循环时间的延长，血小板活化增加，血管内皮细胞损伤加重，且两者之间互为因果。

The relation between P-selection and Plasma D-dimer during extracorporeal circulation

Objective To explore the relation between platelet activation and damage of endothelial cells. Methods The blood samples were obtained through venous catheter from 7 patients undergoing elective cardiac operation for valvular replacement at five different time points during extracorporeal circulation and after extracorpo- real circulation. The presence of in vitro platelet activation was assessed by using flow cytometry for detecting the positive rate of P-selection and the fluorescent density on platelet membrane and ELISA was using to determine the plasma levels of P-selection. Results The positive rate of P-selection on platelet membrane and the plasma level of P-selection and Plasma D-dimer significantly increased during extracorporeal circulation, with a peak at 1 hour after extracorporeal circulation beginning, and decreased after extracorporeal circulation. The correlation between each other was significant among these three parameters. The change of fluorescent density of P-selection at differ- ent time points was tiny. Conclusion With the extending of extracorporeal circulation time, platelet activation in- creases and the damage of the endothelial cells becomes more obvious. Platelet activation and the damage of the endothelial cells affect reciprocally.