What kinds of operations are likely to cause massive bleeding?

Surgeries of the lung, heart, pancreas, prostate gland, uterus, spleen, kidney, breast cancer, etc., which often enhance fibrinolysis, are likely to cause massive bleeding.

Why does patient bleed easily during operation?

Because the fibrinolysis is accentuated by stress associated with invasive surgical procedure. There are a lot of stimuli such as anxiety, anesthesia, blood loss, irradiation, administration of anticancer drugs, etc. Those stimuli and various conditions such as weakness of the patient may combine to abnormal bleeding

What is the mechanism of the fibrinolytic system?

The fibrinolytic system is a physiological reaction that is invoked at the final stage of the hemostatic mechanism. It decomposes fibrin, the end product of the coagulation system, which is therefore called “fibrinolytic system”. There is plasminogen in the plasma, and it is converted to the active enzyme plasmin as often as required. Plasmin is a strong protease which effectively decomposes fibrin in blood. Plasminogen is activated by serine protease called plasminogen activator (PA). There are two types of plasminogen activator in the living body : urokinase PA (u-PA or UK) and tissue PA (t-PA). On the other hand, alpha 2 plasmin inhibitor (α 2-PI) and PA inhibitor (PAI) inhibit activation of plasmin and PA, respectively thus controlling activation of the fibrinolytic system.

What kinds of blood coagulation factors are there?

More than 10 kinds of blood coagulation factors are involved in coagulating blood. If any one of the coagulation factors dose not work well, it takes long before blood coagulates, or if it coagulates, the coagulation is not firm enough. Hemophilia, known as a typical disease with bleeding problems, is caused by factor VIII or factor IX deficiency.

What is the mechanism of blood coagulation?

When endothelial cells in a vessel are injured, platelets gather around the site (coagulation), adhere to each other changing their forms (adhesion), and block the broken vessel temporarily. This triggers blood coagulation. Injured endothelial cells and platelets act on blood coagulation factors in blood plasma, and fibrinogen transforms into filiform fibrins, causing blood coagulation. The process of blood coagulation is attributable to two types of actions : autogenous action mainly by constituents of blood and exogenous action associated with components in the injured tissue.

What is the mechanism of blood coagulation?

When endothelial cells in a vessel are injured, platelets gather around the site (coagulation), adhere to each other changing their forms (adhesion), and block the broken vessel temporarily. This triggers blood coagulation. Injured endothelial cells and platelets act on blood coagulation factors in blood plasma, and fibrinogen transforms into filiform fibrins, causing blood coagulation. The process of blood coagulation is attributable to two types of action: autogenous action mainly by constituents of blood and exogenous action associated with components in the injured tissue

What is the minimum amount of bleeding which may require blood transfusion?

A person may not have significant symptoms as long as the amount of bleeding is up to 15% of the circulating blood owing to the compensatory effect of the living body. When the amount of bleeding is 20% to 30%, it’s impact is significant and blood transfusion is required. It is said that hemorrhagic shock occurs in no time, when more than 30% of circulating blood is lost.