Haemostasis mechanisms

Haemostasis is the mechanism activated after damage to the blood vessel wall that ensures that blood loss is restricted. Blood platelets are are activated and adhere to elements on the damaged lumenal surface of the vessel, eventually forming a platelet plug that stops the leakage of blood. Fibrinolytic mechanisms later produce lysis of the platelet mass when repair of the vessel has occurred. 

Blood plays various vital roles within the body and it is not surprising that a number of processes have evolved capable of effectively maintaining haemostasis (the rapid arrest of blood loss upon vascular damage, in order to maintain a relatively constant blood volume). In humans, three main mechanisms underline the haemostatic process ... 

Hemker HC, Kessels H. Feedback mechanisms in coagulation. Haemostasis 1991 21 189-196. 

Viero P, Cortdaza> S, Barbui T, Gaetano G. Defective platdd aggregation induced by platdd activating factor in myeloproliferative disorders deficiency of an a irin-independent mechanism. Haemostasis 1986 16 27-33... 

Ruggeri ZM Mechanisms initiating platelet thrombus formation. Thromb Haemostasis 78 611-616, 1997. 

Occlusive vascular disease is a major cause of morbidity and mortality.There is now better understanding of the mechanisms by which the haemostatic system ensures blood remains fluid within vessels, yet forms a solid plug when a vessel is breached, and of the ways in which haemostasis may be altered by drugs to prevent or reverse (lyse) pathological thrombosis. 

Z. M. Ruggeri Mechanisms initiating platelet thrombus formation. Thrombosis and Haemostasis 78, 611 (1997) [published erratum appears in Thrombosis and Haemostasis 78, 1304 (1997)] [see comments]. 

Haemostasis is a protective mechanism to stop bleeding from damaged blood vessels. The normal homeostatic control of bleeding consists of three components. If there is a defect in any of these then bleeding will result. 

Pendurthi, U.R., F. Meng, N. Mackman, and L.V.M. Rao. 2002. Mechanism of resveratrol-mediated suppression of tissue factor gene expression. Thrombosis and Haemostasis 87 155-162. 

There are three types of endoscopic treatment available for haemostasis namely injection, thermal, and mechanical methods (Fig. 3.47). The therapeutic end-points in those with active bleeding are cessation of bleeding and to reduce or eliminate the risk of re-bleeding. The role of endoscopic treatment as a prophylaxis in non-bleeders is less clear. 

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