hemostasis Physiology presentation for sem 1 bsc nursing.pptx

Physiology

1. Hemostasis

2. 1. introduce hemostasis 2. describe mechanisms of hemostasis Objective

3. Definition = an injury cause rupture of the vessel resulting in hemorrhage . The body mechanisms try to arrest the bleeding. This is called hemostasis

4. Hemostasis is achieved by several mechanisms 1 . Vascular construction 2 . Formation of a platelet plug 3 formation of blood clot 4 . Formation of fibrous tissue in the clot

5. 1 . Vascular constrration 1. Blood vessels is ruptured or cut 2. Automatic construction vessel 3. Reduce the blood flow Vasoconstriction is produced by nervous reflex , local myogeni reflexes , humoral factors released from traumatized tissues. And blood platelet

6. 2. Formation of a platelet plug. If the damage in the blood vessels is small , it is sealed by the platelet plug A . Resting state B . Initiation C. Extension D.prepatuation

7. Formation of blood clot 1. this is a powerful mechanism for hemostasis . 2. In several trauma there is ruptur of the blood vessels and blood gets exposed to exterior . 3. Blood when it is shed , froms a semisolid jelly like substance in about 15-20 sec . Within 3-6 min. 4. The opening in the vessel is filled with clot. 5. After 20 min To an hour , the clot retracts and completely seals the defect in the blood vessels.

8. Formation of fibrous tissue in the clot 1. fibroblasts re formed within few hours following Clot formation 2. Later in 1-2 weeks , clot is completely organized into the fibreus tissue 3. The clot dissolves by the action of special enzyme. 4. This occurs in places where the clot is not required and patency Of the vessel has to be maintained

9. Summary Reference B.D chaurasia “ Applied anotomy and physiology editing 1 st 2022. CBS Publisher , page no. 40