Describe what happens during platelet plug formation in haemostats
If there is a break in the blood vessel wall then the platelets can get access to the surrounding tissue around the blood vessel. If platelets get out and make contact with collagen they react with collagen and become active. Activated platelets contract and release enzymes that act on arachadonic acid and convert it into thromboxane A which activates more platelets. This means a POSITIVE FEEDBACK SYSTEM has been set up. Activated platelets become sticky and stick together and to the wall of the blood vessel with the help of von Willedbrand factor (a type of protein anchored in the blood vessel wall) to form a platelet plug which is held on to the site of damage.