Studies in Bloodstain Pattern Analysis

 

 

 Through my studies I have found that the clotting process is quite complex. I still do not fully understand the entire process, but I'm sure it will eventually sink in. Here is what I know so far. Blood, while traveling through the circulatory system stays in a liquid (soluble) form. However, when there is a breach to the Circulatory System a chain of events are put into motion.

First, Platelets (Thrombocytes) are activated when they come into contact with Collagen, which is located in the blood vessel wall at the site of the injury/breach. Once this occurs, the Platelets start to change their shape by forming spines, becoming sticky and attach themselves to the injury site. Platelets also release a chemical substance which causes a vascular contraction and/or constriction at the site of injury, thereby reducing the breach to the circulatory system. While the Platelets are busy at work, Fibrinogen, a soluble glycoprotein located in the plasma, is converted to Fibrin in a non-soluble form. The Fibrin creates a mesh-work of strands at the wound site securing and trapping Red blood cells (Erythrocytes) and Platelets alike creating a blood clot.                                                                                                                              Blood starting to clot.