Hemostasis: Coagulation and Factor Xii Contact
HEMOSTASIS
Hemostasis: drives from the Greek meaning “The stoppage of blood flow”. a process which causes bleeding to stop, meaning to keep blood within a damaged blood vessel. It is the first stage of wound healing.
Hemostasis can be divided into two stages: Primary and Secondary. 1- Primary hemostasis includes the platelet and vascular response to vessel injury. 2- Secondary hemostasis includes the coagulation factors response to such injury. Together, platelets, vessels, and coagulation factors combine to stop bleeding and allow for vessel repair through formation of a stable fibrin-platelet plug at the site of injury.
Primary Means, it is individual there is no dependence, But Secondary will always depends on Primary, primary first should complete, There is no precondition to primary, but for Secondary Primary is the Precondition, first there should do primary, then only it would able to do secondary. * Primary hemostasis is characterized by vascular contraction, platelet adhesion and formation of a soft aggregate plug. It begins immediately after endothelial disruption. Injury causes temporary local contraction of vascular smooth muscle. Vasoconstriction slows blood flow, enhancing platelet adhesion and activation. Secondary hemostasis Responsible for stabilizing the soft clot and maintaining vasoconstriction. Vasoconstriction is maintained by platelet secretion of serotonin, prostaglandin and thromboxane. The soft plug is solidified through a complex interaction between platelet membrane, enzymes, and coagulation factors.
Coagulation factors are produced by the liver and circulate in an inactive form until the coagulation cascade is initiated. The cascade occurs in steps. The completion of each step activates another coagulation factor in a chain reaction which leads to the conversion of fibrinogen to fibrin
The clotting cascade is made up of a number of protein factors which ultimately generates fibrin. There are 2 pathways by
Hemostasis: drives from the Greek meaning “The stoppage of blood flow”. a process which causes bleeding to stop, meaning to keep blood within a damaged blood vessel. It is the first stage of wound healing.
Hemostasis can be divided into two stages: Primary and Secondary. 1- Primary hemostasis includes the platelet and vascular response to vessel injury. 2- Secondary hemostasis includes the coagulation factors response to such injury. Together, platelets, vessels, and coagulation factors combine to stop bleeding and allow for vessel repair through formation of a stable fibrin-platelet plug at the site of injury.
Primary Means, it is individual there is no dependence, But Secondary will always depends on Primary, primary first should complete, There is no precondition to primary, but for Secondary Primary is the Precondition, first there should do primary, then only it would able to do secondary. * Primary hemostasis is characterized by vascular contraction, platelet adhesion and formation of a soft aggregate plug. It begins immediately after endothelial disruption. Injury causes temporary local contraction of vascular smooth muscle. Vasoconstriction slows blood flow, enhancing platelet adhesion and activation. Secondary hemostasis Responsible for stabilizing the soft clot and maintaining vasoconstriction. Vasoconstriction is maintained by platelet secretion of serotonin, prostaglandin and thromboxane. The soft plug is solidified through a complex interaction between platelet membrane, enzymes, and coagulation factors.
Coagulation factors are produced by the liver and circulate in an inactive form until the coagulation cascade is initiated. The cascade occurs in steps. The completion of each step activates another coagulation factor in a chain reaction which leads to the conversion of fibrinogen to fibrin
The clotting cascade is made up of a number of protein factors which ultimately generates fibrin. There are 2 pathways by