Ischemia (synonym: local anemia, local anemia) - reduction of blood supply to an organ or tissue due to the limited inflow of arterial blood to the tissue under normal or even increased outflow from him venous blood. Cause ischemia is an obstacle in the artery on the path of blood flow: reflex spasm of the vessel blockage inside tumor or from outside. In line with this, there are angiospastic, obstructive and compression ischemia.
Angiospastic ischemia develops as a result of reflex narrowing of the vessel under the action of various stimuli (see Angiospasm.
Obstructive ischemia often called a thrombus or embolus, as well as some sclerotic or inflammatory processes in the vessel wall, reducing its clearance [for example, obliterating endarteritis (see)].
Compression ischemia is a result of compression of a vessel of the tow, a scar, a tumor, exudation, a parasite, a foreign body.
Often there is a combination of various forms of ischemia. During ischemia dramatically decreases the amount of blood circulating in the body: below the narrowing sopostavit vessels, blood pressure drops, disrupted power as the vascular wall, and the body, resulting in him having the phenomenon of oxygen starvation, the volume of the body decreases, its temperature drops, appear pain. In this ishemizirovanna the body there is a metabolic disorder, disorder of the function. Prolonged ischemia occurs necrosis (see), unless develops collateral circulation, which often can be fully compensated for the contraction of the main vascular bed. In the clinic the result of ischemia may be a heart attack (see) of the relevant body.
The outcome of ischemia depends on its duration, degree of stability tissue to hypoxia, the state of collateral circulation, as well as the functional state of the fabric itself.