Blood circulates throughout the body, supplying nutrients everywhere and taking away waste, so it must be maintained under normal circumstances. However, when a blood vessel is injured and ruptured, the body will produce a series of reactions, including vasoconstriction to reduce blood loss, platelet aggregation to block the wound to stop bleeding, and activation of coagulation factors to form a more stable thrombus to block blood outflow and The purpose of repairing blood vessels is the body's hemostasis mechanism.

Therefore, the body's hemostatic effect can actually be divided into three parts. The first part is produced by the interaction between blood vessels and platelets, which is called primary hemostasis; the second part is the activation of coagulation factors, and the formation of reticulated coagulation fibrin, which wraps the platelets and becomes a stable thrombus, which is called secondary hemostasis, which is What we call coagulation; however, when the blood stops and does not flow out, another problem arises in the body, that is, the blood vessels are blocked, which will affect the blood supply, so the third part of the hemostasis is The dissolving effect of thrombus is that when the blood vessel achieves the effect of hemostasis and repair, the thrombus will be dissolved to restore the smooth flow of the blood vessel.

It can be seen that coagulation is actually a part of hemostasis. The body's hemostasis is very complex. It can act when the body needs it, and when the blood coagulation has achieved its purpose, it can dissolve the thrombus in an appropriate time and recover. The blood vessels are unblocked so that the body can function normally, which is the important purpose of hemostasis.

The most common bleeding disorders fall into the following two categories:

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1. Vascular and platelet abnormalities

For example: vasculitis or low platelets, patients often have small bleeding spots in the lower extremities, which are purpura.

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2. Abnormal coagulation factor

Including congenital hemophilia and Wein-Weber's disease or acquired liver cirrhosis, rat poisoning, etc., there are often large-scale ecchymosis spots on the body, or deep muscle hemorrhage.

Therefore, if you have the above abnormal bleeding, you should consult a hematologist as soon as possible.