EDEMA EDEMA Water is 60% of the body weight 2/3 of which is intracellular, the rest is interstitial fluid and only 5% is in the plasma. Edema means increase in interstitial fluid. It can also be collection of fluid in body cavity known as effusion. Anasarca is a severe and generalized edema with subcutaneous swelling. The hydrostatic and colloidal osmotic pressures control the movement of fluid between vessels and interstitial space. Normally outflow of fluid from the arteriolar end of the microcirculation is balanced by inflow in the venular end. A small leftover fluid is removed by lymphatics. The edema fluid of hydrodynamic derangement is typically poor protein content transudate with low specific gravity Hydrostatic pressure increase ¨ Local- from impaired venous outflow e.g. deep venous thrombosis ¨ Generalized increase of venous pressure commonly occurs in congestive hear...