Hydrops

Hydrops, hydrops (from Greek hydor-water), accumulation of transudate fluid (see), edema of a cavity. For hydrops of various cavities, special terms exist, for example, ascites - abdominal hydrops, hydrothorax - hydrops of the pleural cavity, hydropericardium - hydrops of the pericardial sac, hydrocele - hydrops of the vaginal cavity of the testicle, hydrocephalus - cerebral hydrops (hydrocephalus internus - hydrops of the cerebral ventricles, externus - accumulation of fluid between the bones of the skull and the brain). The pathogenesis of hydrops has much in common with the pathogenesis of edemas (see); however, for the mechanism of its formation, disturbances in vascular function or changes in blood composition, as well as related changes in the endothelium of cavities, are of primary importance; whereas intratissue factors (hydrophilicity of colloids), which play such an important role in the formation of edemas, may not be taken into account here. Hydrops can be a local manifestation of generalized edema (e.g., of cardiac or renal origin) or be of a local nature. In the latter case, it can secondarily cause general circulatory disorders, accompanied by diffuse edemas; for example, ascites, due to increased intra-abdominal pressure, can impede the outflow of blood from the veins of the lower extremities and thus cause edema of the latter. Local hydrops form either due to mechanical circulatory disturbances (impairment of venous blood outflow) or due to difficulties in lymphatic outflow. Sometimes an inflammatory process leads to hydrops due to the obliteration of communications between cavities caused by it (for example, closure of the foramen of Magendie or the aqueduct of Sylvius as the basis for cerebral hydrops). Finally, hydrops can form due to excessive secretion of fluid into the cavity (cerebral hydrops from enhanced secretory activity of the choroid plexus). The course and prognosis of hydrops depend, mainly, on the speed and degree of development of collaterals (anastomoses between the vena cava and vena portae are particularly important in this regard for abdominal hydrops). The characteristics of the fluid in hydrops - see Transudate. The clinical picture of hydrops and its effect on neighboring organs - see Ascites, Hydropericardium, Hydrothorax, Hydrocele, Hydrocephalus.