What is edema
Edema is defined as abnormal and excessive accumulation of free fluid in the interstitial spaces and serous cavity
What is free fluid in body commonly called? Types
Effusion
Types:
•Ascites in peritoneal cavity
•Hydrothorax in the pleural cavity
•Hydropericardium or pericardial effusion in pericardial cavity
Classification of edema
ACCORDING TO POSITION
Localised eg allergic, pulmonary, cerebral
Generalized eg cardiac, renal , nutritional
ACCORDING TO APPEARANCE
pitting and non pitting
ACCORDING TO ETIOLOGY
cardiac, renal, pulmonary
Mechanisms of pathogenesis of edema
- Decreased plasma oncotic pressure
- Increased capillary hydrostatic pressure
- Lymphatic obstruction
- Increased capillary permeability
- Sodium and water retention
Eg of edema due to decreased plasma oncotic pressure
- Edema of renal diseases example in nephrotic and nephritic syndrome
- Asitis of liver disease example in cirrhosis of liver
- Edema YouTube other causes of hypoproteinemia example in protein losing enteropathy
Eg of edema due to increase capillary hydrostatic pressure
- Edema of cardiac disease example in congestive cardiac failure, constructive pericarditis
- Ascitis of liver disease example in cirrhosis of the liver
- Passive congestion example in mechanical obstruction due to thrombosis of vein of lower legs, varicositis, pregnant uterus, tumor etc
Eg of lymphoedema
- Removal of auxiliary lymph note in radical mastectomy
- Pressure from outside on the main abdominal or thoracic duct
- Inflammation of lymphatics
- occlusion by malignant cells
- Milroy’s disease or hereditary lymphoedema
Eg of edema due to increase capillary permeability
Generalized eg systemic infections, anaphylaxis, certain drugs and chemicals
Localised - inflammatory
Infarction definition
Necrosis involving a major or massive area of any organ or ischaemic origin are called infarction
Causes of infarction
Types of infarct on basis of morphology
- Red or hemorrhagic
- Pale or white
Shock
Condition which results into decrease in effective circulating blood volume leading to decreased blood supply to organs leading to multiple organ failure
