How Platelet Adhesion Occurs

A platelet is the smallest unit or cell fragment found in your blood. They are tiny disc shaped cells that have no nucleus like other cells. The main purpose for their existence is to help the body to stop bleeding after injury. This process is called hemostasis. Platelet aggregation is the process of millions of platelets rushing to the site of injury and forming a plug-like formation to stop your body from bleeding out.

Process

• Platelets are produced during blood formation in your bone marrow. The average lifespan of a platelet is 5 to 9 days. When an injury occurs in the body or on the surface of the skin, special hormones and chemicals are released into the blood stream. These hormones and chemicals, including von Willebrand Factor, Platelet Activating Factor and Thrombin, cause the platelets to become "activated." This means that they come together in clumps.

  Hormones also cause the platelets to change shape and become more spherical and to form "stellates" or become star shaped--with tiny points radiating from the center of each one. When the platelets change shape in this way, it helps them to stick together more effectively, which helps to stem the flow of blood. The platelets also release more hormones, which cause more platelets to stick together at the site of injury to help stop the loss of blood.

Significance

• The formation of a blood clot in this way is a natural and temporary measure that your body uses to stop excess blood loss after an injury. If the process does not work properly due to an illness or condition such as Scotts Syndrome or von Willebrand disease, a very simple cut can lead to excessive bleeding with potentially devastating consequences if not properly treated.

Considerations

• Drugs can also have an effect on platelet aggregation. Aspirin is known to have an effect on platelet aggregation as is the blood thinner Warfarin. For this reason, before surgery, it is vital for surgeons to be aware of any medications that you are on so that they can mitigate any potential risks associated with excessive bleeding during surgery.