Hypermia and Congestion 

Definition: Both of them can be defined as a local increase in volume of blood in a particular tissue. 

 Hypermia 

-  is an active process resulting from an increased inflow of blood into a tissue because of arteriolar vasodilation. 

-  commonly occurs in exercising skeletal muscle or acute inflammation. 

-  Affected tissue becomes red as there is engorgement with oxygenated blood. 

Congestion 

 -  is a passive process resulting from impaired outflow of blood from a tissue.

-  occurs systemically as in cardiac failure or locally as in isolated venous obstruction. 

-  Affected tissue appears blue-red due to accumulation of deoxygenated blood. 

-  In long-standing congestion (also called chronic passive congestion states), poorly oxygenated blood causes hypoxia  → results in parenchyma cell degeneration or cell death. 

a) Pulmonary congestion

Cut surface: hemorrhagic & wet.

1.  Acute pulmonary congestion: 

ƒ-  Alveolar capillaries engorged with blood 

ƒ- Septal edema 

2.  Chronic pulmonary congestion: 

-  Thickened & fibrotic septa 

-  Alveolar spaces contain hemosiderin-laden macrophages resulting in an appearance termed brown indurations.

-  Can result in pulmonary hypertension.

b) Hepatic congestion

1) Acute hepatic congestion: 

- Central vein & sinusoids are distended 

- There may be even central hepatocyte degeneration. 

- Peripheral hepatocytes better oxygenated & develop only fatty changes. 

2) Chronic passive congestion of liver:

-  Central lobules grossly depressed because of loss of cells & appear red brown (nutmeg liver).

-  Hemosiderin laden macrophages 

-  In longstanding hepatic congestion, commonly associated with cardiac failure, there is a grossly evident hepatic fibrosis called cardiac cirrhosis 

References

Bezabeh ,M. ; Tesfaye,A.; Ergicho, B.; Erke, M.; Mengistu, S. and Bedane,A.; Desta, A.(2004). General Pathology. Jimma University, Gondar University Haramaya University, Dedub University.

مواضيع ذات صلة

Acute circulatory failure (cardiogenic shock)

Pulmonary hypertension

Pulmonary thromboembolism

Giant cell (temporal) arteritis

ابيضاض الدم النقوي المزمن Chronic myelocytic leukaemias

Abdominal aortic aneurysm

Infective endocarditis

تليف النقيMyelofibrosis

فقر الدم اللا مصنع ( اللا تنسجي ) Aplastic anemia

Septic shock

Distributive shock

Cardiogenic shock