Blood clotting is the most important ability of an organism to stop bleeding when the walls of blood vessels are damaged, and blood clots dissolve when they are no longer needed. The concept of blood coagulability is inextricably linked with the system of homeostasis, the function of which is to preserve blood. Homeostasis has two mechanisms:
- Primary - vascular-platelet. With it, platelets stick together and form the so-called "white thrombus", in which platelets predominate.
- Secondary - coagulation (he also - coagulation of blood). With it, a dense blockage of the damaged area with a fibrin clot is created, which is also called a "red blood clot". This name was given to him because the fibrin mesh basically consists of erythrocytes.
Thus, the process of blood coagulation is rather complicated and its role in the body is very significant. Any pathology associated with blood clotting can indicate disease and lead to it. It should also be clarified that the final stage of homeostasis is fibrinolysis, in which the blood clot breaks down when the vessel recovers and the need for a fibrin clot disappears.
Indicators for the analysis of blood coagulability
The blood coagulation test is also called a coaguloramma. To take a blood test for clotting, you need to determine the indication for this. In a number of diseases, blood clotting may be impaired, and their presence is the basis for verifying the ability of clotting:
- autoimmune diseases;
- abnormal liver function;
- cardiovascular pathologies;
- diabetes mellitus ;
- hemochromatosis .
Also, coagulation analysis is necessary for certain conditions:
- postoperative or preoperative period;
- control in the treatment of anticoagulants;
- If suspicion of prolonged blood loss is necessary, a check for clotting is necessary.
Interpretation of the blood test for clotting
Before talking about the norm of blood clotting analysis, it should be clarified that in each laboratory these indicators may slightly differ, and therefore the final word is for the attending physician. It should also be understood that the coagulogram rates differ during pregnancy, depending on the trimester.
So, the total blood test for clotting contains 8 norms, which give an estimate of blood clotting:
- Blood test for clotting time. The norm of clotting time is 5-10 minutes (for venous blood, and for capillary - 2 minutes). An increase in the parameter indicates a low coagulability, and a decrease in excess clotting.
- APTTV is an activated partial thromboplastin time. The norm is from 24 to 35 seconds. The increase in time indicates a poor coagulation ability, and a decrease in the time for hypercoagulability.
- The prothrombin index is the prothrombin time, which is read to evaluate the external clotting pathway. The rate is from 80 to 120%. A decrease in the indicator indicates a hypercoagulable, and an increase in the reduced function of blood coagulation.
- Fibrinogen is a protein in the plasma. Normally the indicator is from 5.9 to 11.7 μmol / l. It can increase with inflammation, pregnancy, burns and heart attack. The slide can talk about DIC syndrome or liver diseases.
- Thrombin time is the evaluation of the final stage of coagulation. Normally, this figure is from 11 to 17.8 seconds. With a deficiency of fibrinogen, hyperbilirubinemia, or treatment with heparin, there may be an increase, and a decrease in time - with a large amount of fibrinogen in the blood, or with an ICE syndrome.
- The time of plasma recalcification is normal - from 60 to 120 seconds.
- Plasma tolerance to heparin. Currently, this test is not always used. The norm is from 3 to 11 minutes.
- Retraction of the blood clot. Normally the parameter is from 44 to 65%.
How is the blood clotting test performed?
A blood coagulation test is often performed with an in vitro, but, for example, in the assessment of coagulation of whole blood - thromboelastography, a measurement approximating the conditions of Invivo is possible.
To make a general blood test for clotting, 8 hours before the test is not worth eating. Blood for analysis is taken from the vein to evaluate venous blood. To assess the ability of clotting capillary blood and platelets enough to analyze blood from the finger.