1. Chapter 3 Hemodynamic Disorders, Thromboembolic Disease, and Shock
1.Hyperemia and congestion
2.Hemorrhage
3.Thrombosis
4.Embolism
5.Infarction
6.Shock
7.Edema
Zhu keqing 竺可青
Pathology Department
Zhejiang University School of Medicine

2. 1. Hyperemia and congestion
The terms hyperemia 充血and congestion淤血 both indicate a local increased volume of blood in a particular tissue.
Hyperemia is an active process resulting from augmented tissue inflow because of arteriolar dilation, as in skeletal muscle during exercise or at sites of inflammation. The affected tissue is redder because of the engorgement of vessels with oxygenated blood.
Congestion is a passive process resulting from impaired outflow from a tissue.
生理性充血/病理性充血/减压后充血

3. Congestion/venous hyperemia
定义：器官或局部组织静脉回流受阻，血液淤积于小静脉和毛细血管内。
原因：1 静脉受压，如妊娠子宫。
2 静脉腔阻塞，如血栓形成。
3 心力衰竭，左心衰导致肺淤血，右心衰导致体循环淤血。

4. The outcome of Congestion后果
Congestive edema
Congestive hemorrhage
Chronic congestion-实质细胞萎缩/变性/死亡
Congestive sclerosis

5. Congestion/Venous hyperemia
Heart failure cells
Lung brown duration/brown induration
Nutmeg liver
Congestive liver cirrhosis
In severe, long-standing hepatic congestion (most commonly associated with heart failure), there may even be grossly evident hepatic fibrosis (cardiac cirrhosis). 淤血性肝硬化

7. 2. Hemorrhage 出血
Hemorrhage may be external or may be enclosed within a tissue; accumulation of blood within tissue is referred to as a hematoma血肿.
Minute 1- to 2-mm hemorrhages into skin, mucous membranes, or serosal surfaces are denoted as petechiae 瘀点.
Slightly larger (≥3 mm) hemorrhages are called purpura 紫癜.
Larger (>1 to 2 cm) subcutaneous hematomas (i.e., bruises) are called ecchymoses 瘀斑.
Large accumulations of blood in one or another of the body cavities are called hemothorax, hemopericardium, hemoperitoneum, or hemarthrosis (in joints). Patients with extensive hemorrhage occasionally develop jaundice from the massive breakdown of red cells and systemic release of bilirubin.

8. 3. Thrombosis 血栓形成
在活体的心脏和血管内，血液发生凝固或血液中某些有形成分凝结成固体质块的过程。
The pathologic opposite to hemostasis is thrombosis; it can be considered an inappropriate activation of normal hemostatic processes, such as the formation of a blood clot (thrombus) in uninjured vasculature or thrombotic occlusion of a vessel after relatively minor injury.
Both hemostasis and thrombosis are regulated by three general components-the vascular wall, platelets, and the coagulation cascade.

10. THROMBOSIS
Pathogenesis. Three primary influences predispose to thrombus formation, the so-called Virchow triad:
(1) endothelial injury;
(2) stasis or turbulence of blood flow;
(3) blood hypercoagulability

11. Virchow triad in thrombosis
1 心血管内膜损伤 （风心/SBE/AS/血管炎）
受损组织释放ADP/内膜下胶元纤维暴露/PGI2/TXA2-----血小板黏结
内膜损伤/内膜下胶元纤维暴露----内源性凝血系统---血液凝固
内膜损伤/释放组织因子----外源性凝血系统---血液凝固
2 血流状态改变 （静脉系统/下肢/心瓣膜/ AS斑块附近）
轴流---涡流
3 血液凝固性增加 （严重创伤/大面积烧伤/恶性肿瘤）

12. 血栓类型 Pale thrombus 白色血栓 Mixed thrombus 混合血栓 Mural thrombus
Red thrombus 红色血栓
Hyaline thrombus/fibrinous microthrombus

13. Fate of the Thrombus 血栓结局
Propagation. The thrombus may accumulate more platelets and fibrin (propagate), eventually leading to vessel obstruction.
Embolization. Thrombi may dislodge and travel to other sites in the vasculature.
Dissolution. Thrombi may be removed by fibrinolytic activity.
Organization and recanalization.
Thrombi may induce inflammation and fibrosis (organization) and may eventually become recanalized; that is, may reestablish vascular flow, or may be incorporated into a thickened vascular wall.
Calcification:phlebolith/arteriolith.

14. Potential outcomes of venous thrombosis

15. 4. Embolism 栓塞
An embolus is a detached intravascular solid, liquid, or gaseous mass that is carried by the blood to a site distant from its point of origin. 循环血液中出现不溶性异常物质（栓子）随血流运行堵塞血管腔的过程。
Almost all emboli represent some part of a dislodged thrombus, hence the commonly used term thromboembolism.
Rare forms of emboli include droplets of fat, bubbles of air or nitrogen, atherosclerotic debris (cholesterol emboli), tumor fragments, bits of bone marrow, or even foreign bodies such as bullets.

16. Pulmonary emboli
小 Most pulmonary emboli (60% to 80%) are clinically silent because they are small. With time, they undergo organization and are incorporated into the vascular wall; in some cases, organization of the thromboembolus leaves behind a delicate, bridging fibrous web.
中-大 Sudden death（saddle emboliom), right heart failure (cor pulmonale), or cardiovascular collapse occurs when 60% or more of the pulmonary circulation is obstructed with emboli.
Embolic obstruction of 中medium-sized arteries may result in pulmonary hemorrhage but usually does not cause pulmonary infarction because of the dual blood flow into the area from the bronchial circulation. A similar embolus in the setting of left-sided cardiac failure (i.e., with sluggish bronchial artery flow), however, may result in a large infarct.
Embolic obstruction of 小small end-arteriolar pulmonary branches usually does result in associated infarction.
多 Multiple emboli over time may cause pulmonary hypertension with right heart failure.

17. Large embolus derived from a lower extremity deep venous thrombosis and now impacted in a pulmonary artery branch

18. AIR EMBOLISM
空气栓塞 Gas embolism 100ml
Decompression sickness减压病
/Caisson disease沉箱病
/Diver’s disease潜水员病
高压---低压/气体释放（氮气栓塞）

19. 5. Infarction
An infarct is an area of ischemic necrosis caused by occlusion of either the arterial supply or the venous drainage in a particular tissue.
In the United States, more than half of all deaths are caused by cardiovascular disease, and most of these are attributable to myocardial or cerebral infarction.
Pulmonary infarction is a common complication in a number of clinical settings, bowel infarction is frequently fatal, and ischemic necrosis of the extremities (gangrene) is a serious problem in the diabetic population.
Nearly 99% of all infarcts result from thrombotic or embolic events, and almost all result from arterial occlusion.

20. 梗死形成的原因和条件
1 血栓形成
2 动脉栓塞
3 动脉痉挛
4 血管受压
5 供血血管类型
6 局部组织对缺血的敏感程度

21. Morphology 1 梗死灶形状 2 质地 3 颜色
Infarcts are classified on the basis of their color (reflecting the amount of hemorrhage) and the presence or absence of microbial infection.
red (hemorrhagic)
white (anemic)
septic or bland.

23. White (anemic) infarcts occur with arterial occlusions in solid organs with end-arterial circulation (such as heart, spleen, and kidney),
where the solidity of the tissue limits the amount of hemorrhage that can seep into the area of ischemic necrosis from adjoining capillary beds.

24. Remote kidney infarct, now replaced by a large fibrotic cortical scar