Monday, January 9, 2012
Minor factors which may play a secondary part in the production of edema include capillary permeability secondary to anoxaemia and reduction in colloid osmotic pressure. The latter may be due to hypoproteinaemia resulting from anorexia, malabsorption from venous congestion in the infesting, defective metabolism from congestion of the liver and perhaps to loss of protein in the urine or in transudates. Cardiac edema usually occurs in the dependent parts of the body in the first place, i.e. it is found in the loose tissues round the ankles if the patient is up and about or in the sacral region if confined to bed. ASCITES is usually a later manifestation of failure than peripheral edema but tends to be especially prominent in constrictive pericarditis and whenever prolonged cardiac failure has led to cirrhosis of the liver, owning to the degree of congestion in the portal circulation. The inability of the right ventricle to deal with the increased venous return to the heart is also reflected in engorgement of the liver which becomes enlarged, tender and often pulsating. In the early stages there may be abdominal pain from stretching of the capsule.