Question

For this assignment, you will be describing hemostasis and associated disorders.

Your assignment must include the following:

1. Description of how the blood system works to stop bleeding (hemostasis).

2. Summary of the clotting cascade including a description of the intrinsic, extrinsic, and common pathways, and an overview of clotting factors.

3. Discussion of how 2 different anticoagulant medications work to stop clotting.

Answer 1

1. Platelets are tiny blood cells that help the body form clots to stop bleeding. If one of the blood vessels gets damaged, it sends out signals to the platelets. The platelets then rush to the site of damage. they form a plug (clot) to fix the damage.

2.clotting cascade includes ;

• formation of thromboplastin (prothrombin activator) .
• prothrombin and thrombin are produced and calcium is released.
• thrombin produces fibrinogen and fibrin .
• fibrin helps form blood clot (clot retraction)

Coagulation can be takes place through intrinsic or extrinsic pathways.

• The intrinsic pathway can be initiated by events that take place within the lumen of blood vessels. The Intrinsic pathway requires only elements (clotting factors, Ca++, platelet surface etc.) found within, or intrinsic to the vascular system.
• The extrinsic pathway is the other route to coagulation. It requires Tissue Factor (tissue thromboplastin), a substance which is extrinsic or not normally circulating in the vessel. Tissue Factor is released when the vessel wall is ruptured.

clotting factors are:

• Factor I - fibrinogen
• Factor II - prothrombin
• Factor III - tissue thromboplastin (tissue factor)
• Factor IV - ionized calcium ( Ca++ )
• Factor V - labile factor or proaccelerin
• Factor VI - unassigned
• Factor VII - stable factor or proconvertin
• Factor VIII - antihemophilic factor
• Factor IX - plasma thromboplastin component, Christmas factor
• Factor X - Stuart-Prower factor
• Factor XI - plasma thromboplastin antecedent
• Factor XII - Hageman factor
• Factor XIII - fibrin-stabilizing factor

3.Anticoagulants such as heparin or warfarin (also called Coumadin) slow down your body's process of making clots.

Anticoagulants suppressing the synthesis or function of various clotting factors that are normally present in the blood. Such drugs are often used to prevent the formation of blood clots (thrombi) in the veins or arteries or the enlargement of a clot that is circulating in the bloodstream.