Mechanism of mesenteric edema
Mechanisms of edema development. The main factors of edema development
Hemodynamic edema develops when.
- Decreased resorption of the interstitial fluid in postcapillaries and venules;
- increased filtration of plasma in the arterial part of the capillaries;
- increase of BCC.
Lymphodynamic edema develops due to the difficulty of the outflow of lymph from the tissues resulting from:
- mechanical lymphatic insufficiency (mechanical compression, spasm, partial or complete obturation of lymphatic vessels or an increase in central venous pressure);
- dynamic lymphatic insufficiency (excessive lymphatic formation, especially with pronounced hypoproteinemia and weakness of pumping function of smooth muscle elements of lymphangions).
Oncotic edema develops for the following reasons:
- reduction in oncotic blood pressure (mainly due to a deficiency of more hydrophilic albumins);
- Increased oncotic pressure of the interstitial tissue (mainly due to increased vascular wall permeability or damage to cell-tissue structures).
Osmotic edema occurs for the following reasons:
- increased osmotic pressure(osmolality) of the interstitial fluid as a result of damage to cell-tissue structures, increased dissociation of salts, organic substances and compounds, enhancement of ion transport, especially sodium from the blood;
- Decrease in osmotic pressure in blood plasma as a result of parenteral administration of a significant volume of hypoosmolar solutions and / or excessive formation of ADH;
- a combination of both factors.
At the base of membranogenic edema It develops as a result of an increase in the permeability of microvessel walls resulting from:
- development of acidosis in these vessels and surrounding tissues;
activation of hydrolases;
- change in the volume and location of endotheliocytes;
- overgrowth of the vessel walls due to excessinflow of arterial blood and, especially, insufficient outflow of blood through venules and veins, as well as lymphatic microvessels. Treatment of edema should be comprehensive. Therapeutic measures:
- effective treatment of the underlying disease;
- restriction of excess intake of water and salts, especially Na +;
- use of diuretics and saluretics;
- decrease in the increased synthesis of ADH and RAAS activity;
- Increase in coloid-osmotic pressure (by prescribing protein preparations and blood substitutes) with the development of hypoproteinemia;
- appointment of capillary-strengthening,membrane stabilizing drugs: vitamins C, P, E, various other antioxidants, as well as antihypoxants, glucocorticoids, calcium preparations, especially with broken (often increased) permeability of membranes, vessels and tissues, etc.