What does hyperaemia and congestion have In common?
They refer to the increase in blood volume within a tissue
Hyperaemia
Active process of increased blood inflow by arteriolar dilation
When does hyperaemia happen?
During inflammatory response or during exercises for muscles
Congestion
Passive process with impaired blood outflow from tissue
When does congestion happen?
Cardiac failure or during venous obstruction
What can Chronic congestion cause?
It causes inadequate perfusion and hypoxia leading to cell death and tissue fibrosis
Chronic congestion causes elevated intravascular pressure what does that cause?
It can cause Oedema and if the capillaries rupture it can cause focal haemorrhage
Characteristics of acute pulmonary congestion
- blood filled alveolar capillaries
- Alveolar septal oedema
- Intra alveolar haemorrhage
Characteristics of chronic pulmonary congestion
- septa become thickened and fibrotic
- Alveolar spaces contain numerous macrophages laden with hemosideren (heart failure cells) derived from phagocytosed red blood cells
Chronic pulmonary congestion can be due to?
Left sided heart failure or chronic pulmonary Edema
Acute hepatic congestion characteristics
- The central vein and sinusides are filled with blood
- Maybe central hepatocyte dropout due to necrosis
Chronic hepatic congestion characteristics
- red brown central regions of the lobules
- Depressed central region making Surrounding area more elevated
- Presented as more tan fatty liver appearance called (nutmeg liver)
What is chronic hepatic congestion associated with?
Right heart failure
