兔常温体外循环中大剂量乌司他丁对凝血和纤溶系统的影响

目的观察兔常温体外循环（extracorporeal circulation，ECC）前应用大剂量乌司他丁对凝血和纤溶系统的影响。方法20只大耳白兔随机分成2组：乌司他丁组（U组，n=10）和对照组（C组，n=10）。建立兔常温ECC模型，U组在ECC前给予乌司他丁10×10^4U／kg，C组给予等量生理盐水。ECC转机30min，流量为180～300ml／min，肛温维持在36．5℃-37．5℃。分别记录ECC前、停机、停机后1h、2h和3h的血流动力学指标，测定活化部分凝血激酶时间（Am）、凝血酶原时间（PT）、纤维蛋白原（FIB）和D二聚体（D—D）。结果两组PTECC后均较ECC前显著延长（P〈0．05），两组间胛在停机后3h时有统计学差别，C组长于U组（P〈0．05）。两组APTT ECC后也均较ECC前显著延长（P〈0．01），同时间点U组APTT较C组延长更为明显（P〈0．05）。两组血浆FIB含量ECC后均较ECC前显著降低（P〈0．01），同时间点C组较U组下降更明显（P〈0．05）。ECC后两组血浆D—D浓度较ECC前显著升高（P〈0．05），同时间点C组D—D浓度升高较U组更为显著（P〈0．05）。结论ECC后凝血因子消耗使APTr和Prr延长，纤溶亢进使血浆FIB含量下降，DD浓度升高。ECC前应用大剂量乌司他丁可减少ECC中凝血因子的消耗，抑制纤溶系统的过度激活，改善ECC术后凝血功能。提示ECC前应用大剂量乌司他丁具有血液保护功能。

Effect of Large Dose of Ulinastatin on Coagulation-Fibrinolysis System during Normothermia Extracorporeal Circulation in Rabbits

OBJECTIVE To investigate the effect of large dose of ulinastatin on coagulation - fibrinolysis system after extracorporeal circulation（ECC） by establishing the rabbit model of normothermia ECC. METHODS Twenty rabbits were randomly assigned to control group （Group C, n = 10 ） and experiment group （Group U, n = 1Q）. The rabbits in Group U were administered ulinastatin 10 × 10^4 U/kg before ECC, while in Group C were received same volume of saline at the same time. All rabbits were undergoing ECC for 30 min at perfusion flow of 180 -300 ml/min, with rectal temper- ature maintained from 36.5℃ to 37.5℃. Hemodynamic parameters were recorded before ECC, at termination of ECC, 1 hour, 2 hour and 3 hour after ECC. APTT, PT, FIB and D - dimer were determined at the above time point respectively. RESULTS APTTs were prolonged after ECC in both Group U and C （ P 〈 0.05 ） , but APTTs after ECC in Group U were significantly longer than those in Group C respectively（ P 〈 0.05 ）. PTs were prolonged after ECC in both Group U and C（ P 〈0.05）. There was significant difference in PTs between Group U and Group C at 4 h after ECC. The latter was significantly longer than the former（ P 〈 0.05 ）. All levels of FIB in both Group U and C were decreased after ECC （ P 〈 0.05 ）, and the levels of FIB after ECC in Group U were obviously higher than those in group C respectively （ P 〈0. 05）. All concentrations of D - dimer in both Group U and C were increased after ECC （ P 〈 0. 05）,but the concentrations of D - dimer after ECC in Group U were substantially lower than those in Group C respectively（ P 〈 0.05）. CONCLUSION Over consumption of blood coagulation factors during ECC results in prolonged APTT and PT. Hyperfibrinolysis decreases levels of FIB, increases concentrations of D - D. Administration of large dose of ulinastatin before ECC can reduce the consumption of blood coagulation factors during ECC, inhibit excessive activation of fibrinolysis system, and subsequently promot