Coagulation

Blood coagulation pathway

Coagulation is a process that plays a large role in the hardening and thickening of blood to form a clot.

Purpose

Coagulation plays a crucial role in blood clot formation, which is essential for preventing excessive bleeding and maintaining hemostasis. Coagulation involves a series of enzymatic reactions that result in the hardening and thickening of blood, ultimately leading to the formation of a clot or thrombus.

Coagulation Cascade

The coagulation process can be divided into two pathways: the intrinsic pathway and the extrinsic pathway. Both pathways ultimately converge at a common pathway that leads to the formation of a fibrin clot.

• Intrinsic pathway: Also known as the contact activation pathway, it is initiated by damage to the blood vessel wall or exposure to collagen. This pathway involves a series of clotting factors, such as factor XII, XI, IX, and VIII.
• Extrinsic pathway: Also known as the tissue factor pathway, it is initiated by the release of tissue factor (TF) from damaged tissue. This pathway primarily involves clotting factors VII and X.
• Common pathway: The intrinsic and extrinsic pathways converge at the activation of factor X, which subsequently activates prothrombin to form thrombin. Thrombin then converts soluble fibrinogen into insoluble fibrin strands, which form the basis of a blood clot.

Blood Clot Formation

Fibrin strands created during the coagulation cascade intertwine with one another, creating a mesh-like structure that traps blood cells, platelets, and plasma. This process, along with platelet aggregation, forms a stable clot that helps to seal the damaged blood vessel and prevent further bleeding. After the vessel has healed, the clot is gradually dissolved by a process called fibrinolysis, which restores normal blood flow.

References

Coagulation Resources
Latest articles Most recent articles Ongoing trials	Wikipedia