GENERAL HISTOLOGY

Detailed explanation-1: -Edema is defined as a palpable swelling produced by expansion of the interstitial fluid volume; when massive and generalized, the excess fluid accumulation is called anasarca.

Detailed explanation-2: -Interstitial lung edema arises almost exclusively due to an increase of the pulmonary capillary hydrostatic pressure (Pcap), which occurs most commonly in left sided heart failure, hence it is a key element of cardiogenic lung edema.

Detailed explanation-3: -Increased matrix density also increases the excluded volume, which acts to increase the effective interstitial colloid osmotic pressure. In effect, these changes create a suction force that accelerates fluid filtration and the development of edema.