Stein S F, Harker L A
J Lab Clin Med. 1982 Feb;99(2):217-30.
To assess the nature of the hemostatic abnormalities associated with chronic liver disease, we have simultaneously evaluated the kinetic of radiolabeled platelets, fibrinogen, and plasminogen, together wit tests of platelet and fibrinogen function, and coagulation factors in 60 patients with documented, severe but stable cirrhosis of the liver. The mean platelet survival was substantially reduced (5.8 +/- 1.7 days compared with 9.5 +/- 0.6 days in normals, p less than 0.0001) and splenic sequestration of platelets was increased (mean recovery was 47% +/- 18 vs. 65% +/- 5 in normals, p less than 0.0001). Nevertheless the mean platelet count was nearly normal because platelet production was increased nearly twice normal values (mean turnover was 64,000 +/- 33,000 platelets/microliter/day; p less than 0.0001). The mean rate of fibrinogen removal was shortened (p less than 0.0001) and fibrinogen turnover increased about 20% (p = 0.008) while the mean fibrinogen concentration was not different from the results in normal control subjects (p = 0.212). Autologous and homologous fibrinogen disappeared from the circulation at equivalent rates (r = 0.751; p = 0.008), indicating that fibrinogen from cirrhotic patients was not kinetically different from normal fibrinogen. The mean plasminogen survival was significantly shortened (p less than 0.0001), but the mean plasminogen turnover was not increased (p = 0.388). Thus the plasminogen concentration was reduced (p less than 0.0001). For platelets, fibrinogen, and plasminogen, the production rate was the most important determinant of the concentration in the circulation. The administration of heparin to cirrhotic patients improved the survival of fibrinogen but not of platelets. LeVeen valve implantation generally resulted in parallel shortening of both the platelet and fibrinogen survivals and concentrations. Platelet function as assessed by template bleeding time, platelet retention by glass bead columns, and aggregation induced by ADP, epinephrine, and collagen was normal. Fibrinogen determinations by the Clauss and Jacobsson techniques were equivalent, indicating that the ability to polymerize fibrin monomer was not detectably altered. Sixty percent of patients had an abnormal prothrombin time and half that number had a prolonged partial thromboplastin time. Although most patients had a modest decrease in the prothrombin complex coagulation factors, fibrin degradation products were, in general, not elevated in the circulation. The wide range of values observed suggests that a number of different and complex processes may be ongoing in different patients. Overall, the kinetic data suggest that platelets are initially consumed, perhaps on incompletely endothelialized endovascular surfaces in the liver, and that fibrin subsequently forms secondary to local stasis. The absence of increased production of fibrinogen and plasminogen despite shortened survival times reflects the reduced capability of the cirrhotic liver to increase protein synthesis.
为评估与慢性肝病相关的止血异常的本质,我们同时评估了60例确诊为严重但稳定的肝硬化患者体内放射性标记血小板、纤维蛋白原和纤溶酶原的动力学,以及血小板和纤维蛋白原功能测试及凝血因子。血小板平均生存期显著缩短(5.8±1.7天,而正常人是9.5±0.6天,p<0.0001),脾脏对血小板的扣押增加(平均回收率为47%±18%,而正常人是65%±5%,p<0.0001)。然而,血小板平均计数接近正常,因为血小板生成增加近两倍于正常值(平均周转率为64,000±33,000个血小板/微升/天;p<0.0001)。纤维蛋白原清除平均速率缩短(p<0.0001),纤维蛋白原周转率增加约20%(p=0.008),而纤维蛋白原平均浓度与正常对照受试者的结果无差异(p=0.212)。自体和同源纤维蛋白原从循环中消失的速率相当(r=0.751;p=0.008),表明肝硬化患者的纤维蛋白原在动力学上与正常纤维蛋白原无差异。纤溶酶原平均生存期显著缩短(p<0.0001),但纤溶酶原平均周转率未增加(p=0.388)。因此,纤溶酶原浓度降低(p<0.0001)。对于血小板、纤维蛋白原和纤溶酶原,生成速率是循环中浓度的最重要决定因素。给肝硬化患者使用肝素可改善纤维蛋白原的生存期,但不能改善血小板的生存期。LeVeen瓣膜植入通常导致血小板和纤维蛋白原生存期及浓度同时缩短。通过模板出血时间、玻璃珠柱保留血小板以及由ADP、肾上腺素和胶原诱导的聚集评估的血小板功能正常。用Clauss和Jacobsson技术测定的纤维蛋白原结果相当,表明纤维蛋白单体聚合能力未检测到改变。60%的患者凝血酶原时间异常,其中一半患者部分凝血活酶时间延长。尽管大多数患者凝血酶原复合物凝血因子有适度降低,但循环中纤维蛋白降解产物一般未升高。观察到的广泛数值范围表明,不同患者可能正在发生许多不同且复杂的过程。总体而言,动力学数据表明血小板最初被消耗,可能是在肝脏内未完全内皮化血管内表面,随后纤维蛋白因局部血流淤滞而形成。尽管生存期缩短,但纤维蛋白原和纤溶酶原生成未增加,这反映了肝硬化肝脏增加蛋白质合成的能力降低。