弥散性血管内凝血 DIC.ppt

1、弥散性血管内凝血 Chapter 11,中山医学院病理生理教研室 邓宇斌,DIC 一、DIC原因和发病机制 二、促进DIC发生发展的因素（诱发困素） 三、DIC的分期和分型 四、DIC的功能代谢变化（病理生理变化） 五、DIC防治的病理生理基础,第一节 概述,1.血液的凝固与抗凝 流动性 血液运输载体 方向性 内（） 凝血系统 凝血 外（） 血小板 ： 粘 聚 释,凝抗凝 栓塞 失衡 凝抗凝 出血倾向 2.DIC的概念 出血 病因 微血栓 后 休克 致凝 继发纤溶亢进 果 栓塞 溶血 120种病：感染、肿瘤、产科意外,Introduction,DIC is characterized by t

2、he activation of the coagulation system with resultant consumption of a variety of coagulation proteins and platelets, which results in hemorrhagic diathesis and ischemic injury to various tissues.,1.Blood Coagulation It is propagated by an enzymatic events termed coagulation cascade. Contact factor

3、s and the intrinsic pathway Tissue factor and extrinsic pathway,2.Fibrinolysis It is the result of the action of plasmin, a proteolytic enzyme produced from an inert plasma precursor (plasminogen) by the action of various substances termed plasminogen activators.,Humoral plasminogen activators Tissu

4、e plasminogen activators Fibrin or fibrinogen degradation products FDP (Significant biological activity) Fragments X, Y and E (potent antithrombins) Fragments Y and D ( inhibit fibrin polymerization),a a a PC APC TM+ 灭 活 PS(+) C4b C4b PS(-),酶 纤溶 FDP 酶 AT PC 抗 APC TM+a 凝 PS PGI2 VEC TM,第二节 DIC的病因发病学,

5、一、发病原因及机理 1.VEC广泛受损 原因 感染 炎症、免疫损伤（抗磷脂综合征） 高低温、放射损伤 缺血缺氧 酸中毒,Etiology of DIC,1.acute DIC (1)septicemia (2)severe trauma (3)obstetric accidents (4)shock 2.subacute DIC (1)malignant tumors (2)retained dead fetus 3.chronic DIC (1)giant hemangioma (2)systemic lupus erythematosus (SLE),机理 胶原暴露 凝 VEC 释放 受损

6、 合成PGI2TXA2 抗凝 表达TM APC,2.血细胞大量受损 RBC受损 感染：疟疾 原因：溶血 G6PDase：蚕豆病 免疫损伤：异型输血 红细胞素（） 机理： 释 ADP P聚集,WBC激活或受损 坏死 白血病细胞 释 原因 化疗受损 机理 炎症激活 合成 、释 （内毒素、补体、LC、P、AgAb）,P激活或受损 原发性：免疫损伤（抗P抗体抗磷脂抗体） 继发性：DIC 粘（GPb胶原） 聚（GPba fg） TXA2等 P聚、血管收缩 机理 PF111 提供“反应面” aCa2+a aCa2+a PF3 PF3,3.大量致凝物质入血 肿瘤细胞 坏死（包括产科意外） 组织细胞 带负电颗

7、粒物质（内毒素）a 胰蛋白酶 其它丝氨酸蛋白水解酶 a 蝰蛇毒,Pathogenesis of DIC,1.extensive damage of vascular endothelial cells Intrinsic clotting cascade 2.severe tissue injury Extrinsic clotting reaction,3.excessive destruction of the circulating blood cells Generation of procoagulant-active substances Intravascular coagula

8、tion 4.other thromboplastic materials entering the blood Activation of clotting system through the contact of blood with an abnormal surface,the net effects are summarized as follows: 1.loss of plasma fibrinogen as it is consumed by the clotting process and by the action of plasma. 2.loss of other c

9、lotting factors notably , and , as they are used up during the operation of the clotting cascade. 3.fall in the platelet count, as the platelets aggregate and leave the circulation. 4.appearance of fibrin degradation products, as plasmin acts on its substrates.,二、诱因与发生机理 消除致凝物质功能 血液凝血活性抗凝活性 1.单核吞噬细胞

10、系统功能 内毒素血症、糖皮质激素、脾 消除功能 ：致凝物、a 、凝纤产物,2.肝功能严重障碍 灭活活化凝血因子 合成AT、PC 枯否细胞吞噬功能 3.血液的高凝状态 凝血活性 凝血物质：怀孕、肿瘤、应激 抗纤溶：胎盘、药 抗凝活性 抗肝素：H AT、PC、TM等 4.血流郁滞,Predisposing factors to DIC,1.impairment of the clearance mechanism. 2.hypercoagulable state. 3.disorder of microcirculation.,第三节 DIC的分期及分型,高凝期 分期 消耗性低凝期 继发性纤溶亢进

11、期 急性 按发病速度 亚急性 分 慢性 型 代偿型 按代偿情况 失代偿型 过度代偿型,Types of DIC 1.acute DIC Multiside bleeding diathesis Thrombotic complications usually Severe bleeding lead to shock and severe ischemic change in organs 2.subacute DIC Rarely bleeding The evidence of DIC can be detected by laboratory examinations 3.chronic

12、 DIC,Stage of DIC,1.hypercoagulable stage 2.hypocoagulable stage 3.secondary fibrinolytic stage,第四节 临床表现,1.出血 凝血物质消耗性 酶：破坏凝血因子 继发性纤溶亢进 a FDP抗凝：竞争性抑制 a P聚 血管壁受损及溶栓,Consequences of DIC,1.disturbance of coagulation-bleeding (1)the consumption of clotting factors and platelets (2)the activation of fibri

13、nolytic system (3)the production of fibrin degradation products (FDPs),2.休克 出血 回心血量 微血栓阻断通路 CO 心泵功能 :心肌DIC BP 右心后负荷 : 肺DIC 外周阻力: 四个酶系统激活 A、B肽 扩血管物质 FDP (通透性) 激肽 C3a、C5a,2.disturbance of circulation-shock Microthromobus in capillariesand venules Blood returning decrease Cardiac muscle damage Cardiac

14、output and blood volume reduce Effective circulating blood volume decrease Hypotension,3.栓塞 微血栓 器官 功能 BP 供血 障碍 4.溶血：微血管病性溶血性贫血,3.ischemic tissue damage-dysfunction of multiple organs Renal insufficiency Acute adrenal failure Pituitary necrosis Adult or acute respiratory distress syndrome (ARDS) Conv

15、ulsion and coma,4.microangiopathic hemolytic anemia (MHA) characteristic morphologic abnormality of the red blood cells Twisted cells, crenated cells, triangular cells, helmet-shaped cells, and microspherocytes are seen on the blood smear.,Pathophysiological basis of laboratory diagnosis,1.detection of platelet count and its function 2.determination of clotting factors 3.determination of activity of fibrinolysis (1)thrombin time test (TT) (2)pl