The clotting of blood

The clotting of blood and biological defensive reaction that protects the human organism from blood loss in violation of the integrity of the vascular bed. The passage of blood from a liquid state in gelatinous clot (coagulation)that occur in a protein colloidal environment, is a complex enzymatic reaction, involving tissue, plasma and platelet clotting factors (coagulants). The most well-studied plasma coagulation factors, which are proteins. They usually denoted by Roman numerals. Currently known thirteen plasma coagulation factors.
Blood coagulation system is extremely flexible biological system, are in dynamic balance. The excess or deficiency of certain coagulation factors may lead to, for example, hemophilia (see), hemorrhagic diathesis (see), embolic disease (see) and other serious diseases, which are based on the acceleration or deceleration of the process of blood clotting.
Coagulation consists of several phases. The first and most difficult phase is formation of active thromboplastin at destruction of platelets and violation of the integrity of the vascular wall. In this phase involved a number of plasma and platelet clotting factors. In the second phase under the influence of active thromboplastin inactive protein prothrombin in the presence of ions and V, VII and X of the plasma clotting factors become active enzyme thrombin. In the third phase of soluble protein fibrinogen under the action of thrombin is transformed into insoluble fibrin. As a result of formation of a blood clot, which is based on the fibrin, closes the defect of the vessel and stop the bleeding. Further there is the seal of blood clot. In vitro, it appears retraction (compression) blood clot.
In addition coagulants in the blood are also substances that limit or slow down the process of coagulation,- anticoagulants. The main substance, confining coagulation, is the fibrin, which has a huge surface and actively adsorbs on it formed thrombin. In addition, anticoagulant activity has heparin, the synthesis of which occurs in the liver tissue. Besides, there are substances (for example, antitrombina, antitrombogenny), neutralizing some of the clotting factors.
Study of blood coagulation. To determine all phases of blood clotting methodologically difficult. Usually such analyses performed in the laboratories of specially trained doctors-laboratory assistants. In a wide medical practice define the coagulation activity of blood by the time of its collapse and prothrombin complex one-stage method of Quick. These methods are usually used to control the blood coagulation with the introduction of a body of anti indirect actions (fenilin, plantan and others). They are simple, but not fully reflect the state of blood coagulation. Normal values of these tests cannot exclude the presence of the patient's state of Hypo - or hypercoagulation. In those cases, when these studies indicate any deviation from the norm, you need a detailed study of the blood coagulation system to clarify the causes of these violations.
The technique of definition of time coagulation for Mac-Magro. On a watch glass, covered with a thin layer of wax is poured a bigger drop of mineral oil. A needle or disposable lancets produce a shot in a thoroughly cleansed by the spirit the flesh of a finger. Wash speaking drop of blood, gently squeezing out the new drop and nakazyvaet it in the eyedropper from geometra Sali (20 mm3), pre-soaked inside paraffin oil. Blood pipette immediately blown in a drop of oil on the hour glass, this moment is celebrated on the clock as the beginning of the study. Every minute the blood again nakazyvaet a pipette, wiping the tip of the pipette filter paper. Until the blood has not collapsed, it rises in the eyedropper; upon the occurrence of collapse to nanosat it becomes impossible. Normal human blood at temperature 25 degrees folded in 8-12 minutes Define the clotting of blood in this method at the temperature of 15 - 25 degrees.
Single-stage method of determination of prothrombin complex on Quick. The method is based on the determination of the clotting time of plasma adding to it the optimum quantities thromboplastin and calcium chloride. The method allows to judge about the activity of prothrombin and accelerators of its transformation - plasma factors V and VII (prothrombin complex). Reagents: the solution of calcium chloride (1/40 part of molar solution)in a water bath, plasma thromboplastin.
In vidolasco tube, located in a water bath at temperature 37 deg, pour 0.1 ml of plasma and 0.1 ml of device; includes stopwatch. The mixture was incubated for 2 minutes and then add 0.1 ml of calcium chloride solution and determine the clotting time, which in optimal amounts of device and calcium depends on the content in the plasma prothrombin complex.
The content of prothrombin complex in the blood is expressed in the form prothrombin index.
Prothrombin index = (prothrombin time healthy person X100) / (prothrombin time test plasma).
Prothrombin index normal ranges from 95 to 103%.
To determine the cause of the blood clotting disorders produce a number of studies that show the change in the content of those or other components of the coagulation and Universiada blood system (definition of prothrombin, fibrinogen, thromboelastography and others). The results of these samples are triglycerides, characterizing the state of blood coagulation.