"Coagulogram - what is it?" - Patients are asked in surprise, who are sent to take such an analysis. Indeed, ordinary people face such a study infrequently, usually in preparation for a planned operation. This term is familiar to all pregnant women. Analysis of the coagulogram in the process of bearing a child is done every trimester.
Under an incomprehensible word lies the study of blood coagulability. The set of indicators studied may vary depending on the particular laboratory. The analysis is indicative and detailed. In the first case, it is determined only in which link of the coagulation process a violation occurred. A detailed coagulogram is a type of study that, in addition to qualitative ones, also studies quantitative defects. With its help, it is possible to detect platelet disorders, various thrombophlebia, a deficiency of certain coagulation factors, etc.
The set of methods used to obtain the result depends on the clinical picture, the type of pathology, and the goals of the analysis. It should be noted that decoding a blood coagulogram is a great difficulty not only for a layman, but sometimes for a doctor. Usually, in order to make an accurate diagnosis, several correctly selected tests are required.
Blood coagulation process
Let us consider in more detail how the coagulation system functions. At the first stage, with chemical or mechanical damage to the walls of blood vessels, thromboplastin is released - a special substance that triggers the clotting reaction. Then, coagulation factors are activated - special proteins that are always normally present in the blood and provide a thrombus at the site of damage to the vessel wall.
Further, thrombin (a natural component of the coagulation system, formed from prothrombin) activates an inactive fibrinogen protein, turns it into active fibrin, which forms the basis of the clot. Blood elements, including platelets, become "entangled" in the networks of fibrin. As a result, the blood platelets contract and compress the clot, forming a mature thrombus, covering the damage to the vascular wall. In contrast to the blood coagulation system, the anticoagulation system also functions in the body. Together, they allow you to maintain blood in a normal state.
Pregnancy coagulation test
As already noted, every trimester, and in some cases more often, a pregnant woman is given a coagulogram. What is it and why is it needed, future mothers know firsthand. The fact is that during the bearing of the baby, the activity of the coagulation system generally increases. This is a natural process associated with the appearance of the uteroplacental circle of blood circulation. The body of the expectant mother is thus preparing for a possible blood loss during childbirth.
To identify the features of bleeding disorders and some pregnancy complications, a coagulogram is performed. The doctor may ask you to take an analysis at an unplanned time if there are deviations from the normal parameters of hemostasis (blood components and blood vessels, the interaction of which helps maintain the integrity of the vascular walls and stop bleeding in case of damage). Blood for examination is taken in the morning on an empty stomach from a vein.
Decoding blood coagulogram
Only an expert should study the results of the analysis. Without special knowledge, a person will not be able to decipher the indicators of the coagulogram and assess the degree of their deviation from standard values. Let's try to understand the intricacies of the process and talk about the main parameters of the study.
1. Fibrinogen
This is a protein synthesized in the liver that turns under the influence of a certain blood factor into fibrin. This indicator necessarily includes a blood coagulogram. The norm of fibrinogen is 2-4 g / l. If it is increased, then coagulation is increased, and there is a risk of blood clots. Typically, this situation is observed before childbirth, with pneumonia, after surgery, with acute infections and inflammations (tuberculosis, flu), myocardial infarction and stroke (on the first day), with burns, hypothyroidism, and oral contraceptives and estrogens. A decrease in fibrinogen may be due to toxicosis, cirrhosis of the liver or severe hepatitis, a lack of vitamin B12 or C, intake of androgens, anabolics, fish oil, anticoagulants.
2. Activated partial thromboplastin time (APTT)
A coagulogram examines the time during which a blood clot forms after calcium chloride and other substances are combined with plasma. If at least one coagulation factor is below the norm by 30-40 percent, the level of APTT will change. The average rate is 30-40 seconds. Time can increase with a lack of vitamin K, liver diseases. The reason for the increase in the duration of APTT and, as a consequence, the slowing down of coagulation may be hemophilia.
3. Lupus anticoagulant
This parameter always contains a coagulogram. What is this indicator? Now we will tell. These are antibodies IgC and IgM, leading to an increase in APTT. Normally, they should not be produced in pregnant women. Antibodies appear in the case of autoimmune diseases, with gestosis. Pregnancy against the background of such a pathology often results in spontaneous abortion, fetal death, or placental infarction.
4. Prothrombin
It is a complex protein, a precursor of thrombin (a protein that stimulates the formation of blood clots). This is one of the most important indicators of a coagulogram. Prothrombin with the participation of vitamin K is synthesized in the liver. After analyzing the value of this parameter, the doctor can identify pathology of the gastrointestinal tract and liver.
5. Prothrombin time
The time during which in the plasma when thromboplastin and calcium chloride are added to it, a fibrin clot forms. This indicator is expressed in seconds and is normally 11-15.
6. Prothrombin index (PTI)
The coagulogram most often includes this particular parameter, instead of the previous one. This is the ratio of the clotting time of a healthy person to a patientโs plasma, expressed as a percentage. Normally, the prothrombin index should fluctuate between 93-107 percent. Factors of this indicator are synthesized in liver cells; in liver diseases, their number decreases, so IPT can to some extent serve as a parameter for determining the functional state of an organ.
If IPT is increased, then coagulation is increased, and there is a risk of thrombosis. Growth can be observed when taking oral contraceptives and in the last months of bearing a child. A decrease in the prothrombin index indicates a deterioration in the blood coagulation properties. The formation of factors of the prothrombin complex depends on vitamin K, therefore its deficiency, malabsorption in the intestines (with dysbiosis, enterocolitis) can also lead to a decrease in IPT. Also, this can lead to the administration of large doses of acetylsalicylic acid, diuretics.
7. Thrombin time
This is the time during which fibrinogen is transformed into fibrin. Its normative value is 15-18 seconds. An increase in this indicator is observed with congenital fibrinogen deficiency or with severe liver damage. A decrease in the parameter, i.e., a decrease in thrombin time, indicates the presence of paraproteins (proteins of the class of immunoglobulins) or an excess of fibrinogen. Typically, the value of the indicator is monitored during treatment with fibrinolytics or heparin.
8. Antithrombin III
It is a thrombin inhibitor, a protein of the anticoagulant system. It inhibits coagulation processes. The level of the indicator is determined by the binding in the control sample of thrombin (inhibition). The normal value of antithrombin III is 71-115 percent. A decrease in the parameter by 50 percent of the norm carries a risk of thrombosis.
The definition of this indicator is especially important for expectant mothers taking anticoagulants. These drugs are used when carrying a child, when blood coagulation is increased, and there is a threat of the formation of placental insufficiency, abortion.
9. D-dimer
This is an important indicator for the diagnosis of thrombosis, which includes a coagulogram. What does this parameter demonstrate? It allows you to identify the processes of thrombosis and dissolution of fibrin. Normally, the D-dimer is less than 248 ng / ml. The level of the indicator begins to gradually increase already in the early stages of pregnancy. By childbirth, the value of the parameter can exceed the initial one by three to four times. This is considered the norm. A higher rate is found in women with a complicated pregnancy (gestosis), as well as in those who suffer from kidney diseases, diabetes.
10. Platelets
These are blood platelets involved in providing hemostasis. They are formed in the bone marrow. The standard value is 150-400 thousand / ฮผl. In some cases, in healthy women, a decrease in platelet count to 130 thousand / ฮผl may be observed. A significant reduction in the number of these blood elements is called "thrombocytopenia" and occurs as a result of a decrease in the formation of blood platelets, an increase in their consumption or destruction. With insufficient nutrition, platelet formation is reduced. With the DIC syndrome, which will be discussed below, the consumption of the described uniform blood cells increases.
11. DIC
The interaction of platelets, the process of fibrinolysis and coagulation factors provides a balance between anticoagulation and coagulation systems. If any of these links is compromised, quite serious complications can occur during pregnancy. The most dangerous of them is considered disseminated intravascular coagulation. It develops as a result of activation of the fibrinolysis system and coagulation system. In pregnant women, the causes of DIC can be amniotic fluid embolism, premature placental abruption, and endometritis.
12. Antiphospholipid Syndrome (APS)
It is a complex of symptoms that characterize thrombosis (venous and arterial). Women with AFS have a high risk of miscarriage and the occurrence of spontaneous abortion, because in this case, the increase in the number of vessels of the placenta is disturbed, and fetoplacental insufficiency develops. In order to diagnose antiphospholipid syndrome, in addition to increased thrombosis, antibodies to the outer membrane membrane (phospholipids) are also determined.
Finally
The considered indicators of the coagulogram are not exhaustive. As noted above, the selection of specific parameters for the study depends on various factors. The results of the analysis can be obtained within a day after blood donation.