How long does a blood clotting test take? What kind of analysis is this - a coagulogram? Preparing for the test

Why take a blood test for clotting? What are the indications for a coagulogram? What will the decoding of a blood coagulogram tell about? What pathological processes and diseases can be indicated by deviations of certain markers of blood coagulation from the reference values? We will try to answer these questions in as much detail as possible in this article, covering all indicators of blood coagulation.

So, coagulogram with decoding.

fibrinogen

This is the so-called factor I blood clotting. Transforming into fibrin - the insoluble basis of a blood clot - plays a key role in the formation of a blood clot and, thus, in stopping bleeding.

When is a plasma fibrinogen test indicated:

  • As one of the examinations before surgical interventions.
  • In the presence of inflammatory processes.
  • With cardiovascular diseases.
  • During pregnancy for prenatal diagnosis.

Table of reference values, hemostasiogram indicators:

What does an increase in the level of fibrinogen in the blood mean? Fibrinogen is elevated during the development of a heart attack, stroke, pneumonia, cancer, as well as acute inflammation, thyroid dysfunction, and amyloidosis. In addition, exceeding the norm may occur while taking estrogens and oral contraceptives, in case of burns and surgical interventions. Decoding of the analysis should be carried out by a doctor.

In the case of a low level of fibrinogen in the blood, a coagulogram may indicate:

  • lack of vitamins B12 and C;
  • serious pathologies of the liver with hepatitis or cirrhosis;
  • DIC;
  • embolism of newborns (in this case we are talking about embolism with amniotic fluid);
  • toxicosis of pregnant women;
  • myeloid leukemia;
  • polycythemia.

Lower, compared with the norm, will be the level of fibrinogen in the blood plasma during the period of taking anabolics and androgens, as well as fish oil, as a result of snake venom poisoning.

Thrombin Time (TV)

This time is called thrombin because it characterizes the time period during which the fibrin already mentioned by us under the influence of calcium ions turns into a thrombus.

When a blood test is prescribed to determine thrombin time:

  • when it is necessary to determine how sufficient the level of fibrinogen in the blood is and what its effectiveness is, that is, whether the fibrinogen present in the blood copes with its functions;
  • to monitor the effectiveness of treatment with fibrinolytics;
  • to control the condition of patients with DIC;
  • at serious illnesses liver;
  • to confirm miscarriages;
  • to detect fibringen and (or) fibrin breakdown products in blood plasma.

Reference values ​​of the blood coagulogram index:

If the TV on the coagulogram is lowered, this means that blood clots form very quickly, which is fraught with blockage of blood vessels and thrombosis, often leading to death.

Among the reasons for the increase in TV:

  • congenital fibrinogen deficiency;
  • autoimmune diseases;
  • liver failure, hepatitis;
  • the presence of DIC;
  • general hypovitaminosis against the background of hypervitaminosis with vitamin K;
  • therapy with direct anticoagulants;
  • the development of infectious processes in the body;
  • violation of blood circulation.

prothrombin time

This indicator of blood coagulation will tell us how quickly coagulation occurs and a blood clot is formed. Indications for referral for PTV test:

  • general examination;
  • preoperative examination;
  • the likelihood of internal bleeding and hemorrhage;
  • the likelihood of thrombosis;
  • the assumption of violations of hemostasis;
  • diagnostics of pathological processes in the liver;
  • cardiovascular diseases;
  • thromboembolism;
  • therapy with direct and indirect anticoagulants;
  • suspicion of chronic anemia;
  • nosebleeds.

What are the normal values ​​for the coagulogram index Prothrombin time? As a rule, it is 11-16 seconds. During pregnancy, the upper limit is a couple of seconds longer. However, different brands of laboratory equipment may have their own standard indicators depending on the methods and conditions of testing. Decoding of indicators should be carried out by a doctor. When PTV is lowered:

  • in the last three months of pregnancy;
  • with low-dose aspirin therapy;
  • when using oral contraceptives;
  • in the presence of polycythemia (an increase in the number of red blood cells in the blood);
  • in case of deep vein thrombosis.

An increase in PTV compared to the standard value may mean:

  • congenital or acquired insufficiency of certain blood coagulation factors;
  • DIC;
  • treatment with warfarin;
  • progressive hypovitaminosis of vitamin K (against the background of pathologies of the pancreas and gallbladder, imbalance of microflora);
  • an increase in antithrombin in the blood.

The deviation of PTV from the norm in the direction of increase may also be due to the intake of certain antibiotics, laxatives, hormonal drugs and aspirin).

Prothrombin index

Normally, this indicator of a blood test is 95–105%, when analyzing a blood sample according to Quick, it is 78–142%. If the indicator is below the reference value, this may be evidence of:

  • insufficient amount of vitamin K, which affects blood clotting;
  • treatment with coagulants;
  • pathology in the liver;
  • congenital or acquired lack of fibrinogen;
  • congenital deficiency of certain blood clotting factors.

If the PTI on the coagulogram is higher than normal, then this may indicate a deficiency:

  • congenital - prothrombin, plasma Ac-globulin, proaccelirin (labile factor), proconvertin (stable factor), Stuart-Prauer factor;
  • acquired - coagulation factors caused by nephrotic syndrome, amyloidosis, impaired liver function;
  • vitamin K.

And also take place against the background of therapy with direct anticoagulants, the presence of heparin in the blood, leukemic DIC, antibiotic treatment, taking anabolics, laxatives, aspirin, nicotinic acid etc., taking hormonal contraceptives.

Activated partial thromboplastin time

The study of this indicator can be assigned to the patient along with the tests described above. This is usually due to the following reasons:

  • bleeding;
  • heart attack;
  • intestinal necrosis;
  • control of therapy in the presence of DIC;
  • infertility, miscarriages, abortions;
  • examination before surgery;
  • diagnosis of hemophilia;
  • thromboembolism;
  • deep vein thrombosis;
  • damage to the main vessels.

Normal APTT values:

An increase in the APTT value warns of the risk of bleeding against the background of:

  • hemophilia;
  • insufficient amount of vitamin K;
  • the presence of lupus anticoagulant in the blood;
  • genetic abnormalities;
  • acute leukemia;
  • DIC;
  • postpartum hemorrhage.

APVT in the coagulogram below the norm indicates a predisposition to hemophilia, bleeding and thromboembolism as a result of antihemophilic globulin deficiency, thromboembolism, initial stage DIC in a child.

When assessing the APVT indicator in combination with PTT, the decoding of the blood coagulogram can be as follows:

  • the norm of APVT with increased PTT means the likelihood of liver pathologies, vitamin K deficiency and weak function of blood coagulation factor VII;
  • APVT rate + PTT rate in the presence of lupus anticoagulant in the sample is evidence of von Willebrand disease;
  • elevated APVT and PTT, which means we can talk about serious problems with the liver, fibrinogen and prothrombin deficiency;
  • normal PTT + a slight decrease in APTT indicate normal blood clotting or a slight lack of clotting factor.

D-dimer test These coagulation parameters are valuable for their high negative predictive value. The accuracy in this case is up to 98%.

How to evaluate the decoding of the coagulogram in this case? If the D-dimer coagulation parameters are normal, then thrombosis is excluded with practically the specified probability.

Elevated values ​​will indicate that blood clotting is more active and there is a high risk of thrombosis.

A negative result of this test is extremely rare, only in 2% of cases. First of all, when obtaining such a result, possible mistakes even at the stage of material sampling, a re-analysis is done. And even then, the obtained value below the normative threshold may indicate a small thrombus size, a decrease in FAP (plasma fibrinolytic activity or the ability to spontaneously dissolve blood clots) or a high level of PAI–I plasmogen inhibitor activator. However, this is where it starts difficult topic genetics and to understand it, you need a separate article.

Lupus anticoagulant

The specificity of this indicator is that, as such, it is of little significance for diagnosis on its own and is considered by experts as one of the factors in a series of tests. So, with a positive result of the analysis, one can assume the presence of blood clots, oncology, inflammation or AIDS. However, it is possible to make a correct diagnosis only by evaluating a set of indicators.

Coagulogram indicators proteins C

Deficiency of this protein argues the risk of thrombosis and is inherited. The probability of developing this pathology depends on the form of inheritance, which is determined in the process of genetic analysis. Depending on its result, DIC and neonatal purpura (with a homozygous form of gene carriage) may be detected at an early age, or the risk of thrombosis and low sensitivity in acticoagulant therapy in adolescence may increase.

When is a protein C test ordered?

  • with thrombosis;
  • if direct relatives have a congenital deficiency of this protein;
  • on the results of other blood clotting tests.

Reference values ​​of protein C in the coagulogram:

  • activity - 70–130%;
  • amount - > 3 mg / ml or 60 nmol / l.

Protein S

The normal values ​​for these indicators of hemostasiogram in blood plasma are 140%, in free form - 65–144%. At the same time, you need to know that women have slightly less of this protein than men.

The lack of proteins S is the cause of venous thrombosis, especially at a young age.

Plasma heparin tolerance

Normally, this indicator of the coagulogram is 7-15 minutes. If the upper limit of the reference value is exceeded, this indicates a decrease in heparin resistance, which is often the case in cases of liver disease. If the blood coagulogram shows that the test result did not reach the lower normal value, this may indicate oncology, diseases of cardio-vascular system during pregnancy and in the postoperative period.

RFMK or soluble fibrin-monomer complex

The normal value of the test is 3.36-4 mg / 100 ml of plasma. If rfmk is elevated, this may indicate disturbances in the hemostasis system, thrombinemia (excessive number of microthrombi in the vessels).

RFMK can be below normal while taking anticoagulants, as a rule, if the recommended doses are violated, which makes the blood begin to clot poorly.

Duke bleeding time

Normally, bleeding in this sample stops completely within 1.5–2 minutes. This indicator of the coagulogram is diagnostically significant only with a comprehensive assessment of blood tests.

Coagulation according to Lee White

The reference values ​​​​of the indicator fit into the time interval of 4–7 minutes for a glass tube and 15–25 for a silicone tube.

If this indicator of coagulability exceeded the norm, this may indicate a violation of the thyroid gland, anaphylactic shock, blood loss.

This phenomenon can also occur as a result of vascular manipulation.

Deceleration of clotting time in this test often indicates liver disease, severe infections, hemophilia and oncological heparin therapy and treatment with other anticoagulants.

Antithrombin III

This blood test for a coagulogram is indicated for:

  • suggestion of venous thrombosis;
  • after surgery for the removal of a blood clot;
  • with low sensitivity to heparin,
  • as well as in combination with tests for proteins C, S and lupus anticoagulants.

The values ​​of the indicator are normal:

There is also a separate scale of standard values ​​for pregnant women.

If this indicator of the oagulogram is elevated, this may mean:

  • long-term therapy with warfarin, phenylin;
  • lack of vitamin K in the body;
  • the presence of acute viral hepatitis and other liver diseases;
  • the course of the inflammatory process;
  • period of menstruation in women.

Underestimated values ​​indicate:

  • predisposition to thrombotic processes;
  • recent weeks pregnancy;
  • middle of the menstrual cycle.

Coagulation is a complex and very important process in the human body; a coagulogram blood test allows you to control it. Hemostasiogram in adults and children should be deciphered by a doctor. Yes, indeed, this is the lot of a specialist, and quite experienced and qualified. Without sufficient knowledge, it is simply impossible to interpret the indicators of the caogulogram correctly. Therefore, your own interpretation of the results of the coagulogram is not a reason to correct the treatment prescribed by the doctor, otherwise the results may be unpredictable.

In contact with

The normal coagulation parameters in the table include optimal indicators. So, when conducting an analysis, a person receives several numbers as a result. These include APTT, Fibrinogen, Lupus Coagulant, Platelets, Prothrombin, TB, D-Dimer, and Antithrombin III.

If we are talking about an extended analysis, then the following are attributed to these indicators: Prothrombin time, Protein S, Protein C and Willebrand factor.

All these "elements" must have certain numbers. They indicate that everything is normal, or has a slight deviation. In normal form, the indicators should be as follows:

With any deviation, the norm of the coagulogram is not similar to the given data. This phenomenon requires finding out the cause and eliminating the problem itself.

Coagulogram indicators are normal if there are no negative processes in the human body. Moreover, if the patient does not take indirect coagulants, then changing the main "elements" is simply impossible.

If there are deviations, then it is necessary to find out the reason without fail. The fact is that a decrease in some indicators can lead to thrombosis, which is especially dangerous for humans. If we are talking about a pregnant girl, then any deviations can provoke not only the formation of blood clots, but also premature detachment of the placenta. Therefore, the norm of the coagulogram should always be viewed, this will avoid serious complications.

INR coagulogram norm

The norm of the coagulogram depends on many indicators. So, this "element" is a calculated data, thanks to which you can find out the ratio of the patient's prothrombin time to the average prothrombin time. This indicator is necessary for therapy with indirect coagulants.

The fact is that these medicines can worsen blood clotting and lead to serious problems. Patients who are on such therapy should monitor the INR.

Normally, this "element" is less than 1.25. If the figure is underestimated or overestimated, it is necessary to look for the cause of this phenomenon. Basically, a sharp decrease in INR indicates an insufficient effect that anticoagulants give, which requires some intervention. This process can lead to a significant risk of thrombosis. The norm of the coagulogram of the INR indicator should not fluctuate, because otherwise it is harmful to the body and most likely the negative process has already begun.

Fibrinogen norm

The norm of the coagulogram fibrinogen, if violated, can lead to increased bleeding. Under this indicator, a specific protein is hidden. It refers to the main component of a blood clot, which is able to form during blood clotting. Fibrinogen, by virtue of its qualities, is responsible for many functions regarding the coagulation process.

This indicator fluctuates most strongly during pregnancy, and there is nothing to worry about. But still, a woman should be under the supervision of a doctor. Indeed, in some cases, this may indicate the presence of an inflammatory process or the risk of developing cardiovascular complications. All this can occur against the background of increased blood clotting, which is not the norm. In general, this indicator should not exceed 6.5 g / l.

With a significant decrease in it, severe bleeding may develop, which can be congenital. It is worth watching the “element” during pregnancy, and paying special attention to this moment. After all, the norm of the coagulogram of this indicator must be observed.

PTI coagulogram norm

The norm of the coagulogram pti is the ratio of the clotting time of normal plasma to the clotting time of the patient's plasma. This number should be expressed as a percentage and not exceed 78-142%.

This indicator can increase, but only at the risk of developing blood clots. The set number decreases with a tendency to bleed. That is why it needs special attention.

It should be noted that in pregnant women this indicator can vary slightly and this is the norm. True, this may be due to premature detachment of the placenta.

An increase in the index indicates the presence of increased blood clotting. This is not entirely good, because it can lead to the development of cardiovascular diseases. In some cases, the indicator varies due to long-term use of oral contraceptives. In any case, the true cause of such a phenomenon must be determined. The norm of the coagulogram of the prothrombin index must be observed.

RFMK coagulogram norm

The norm of the coagulogram rfmk depends on many things. Basically, this indicator is necessary in order to determine the amount of soluble complexes in the blood.

These "elements" are markers of thrombinemia in intravascular coagulation. This indicator can only be determined manually. Naturally, the procedure is not complicated and is carried out quite quickly. Ideally, there should not be any complexes in the human blood at all.

RFMK is not at all mandatory. Rather, it is done before a serious surgical intervention. This indicator is taken from the blood that was submitted for analysis. The higher the concentration of complexes in it, the higher the risk of intravascular thrombosis. Therefore, RFMC plays a significant role.

Its decrease indicates treatment with heparin. This is quite effective when it is necessary to prescribe heparin prophylaxis or heparin therapy. RFMC norm of coagulogram should not go beyond 0-0.4.

Norm of coagulogram D dimer

The norm of the coagulogram d dimer plays a significant role. So, this indicator is a fibrin breakdown product. It shows violations of the blood coagulation process. This element is especially important in the diagnosis of thrombosis, pregnancy and cancer.

The dimer has always been considered a specific degradation product that is part of the thrombus. According to these data, it is possible to monitor the intensity of the processes of formation and destruction of fibrin clots.

Many factors can affect this figure. Determination of the Dimer level is considered specific. Its level depends on the presence of pathological conditions that can be accompanied by enhanced fibrinolysis. These include various kinds of infections, wound healing, hemorrhagic complications, and similar processes. Normally, Dimer does not exceed 33-726 ng/ml. If there are any violations, then they must be neutralized without fail. Because the norm of the coagulogram of this indicator must be fully observed.

The norm of the coagulogram PV

The norm of the PV coagulogram is another important indicator. Prothrombin time is an "element" that reflects the rate of blood clotting. It is used to diagnose diseases of the blood coagulation system. In addition, it allows you to evaluate the effect of drugs that are aimed at worsening the ability to coagulate.

Normally, this indicative should not exceed 10-13 seconds. Any deviations indicate the presence of pathological processes in the body. An indicator above the norm indicates that there is a low concentration of clotting factors, a lack of vitamin K, as well as liver disease or a violation of its functions.

It is likely that we are talking about the presence of disseminated intravascular coagulation syndrome. This condition can be life threatening, because it does not allow the blood to clot quickly, which can lead to complete non-stop bleeding. An increase in prothrombin time is not a good process. If surgical intervention is necessary, the coagulogram norm for this indicator must be observed.

The norm of the coagulogram during pregnancy

The norm of the coagulogram during pregnancy must be observed without fail. The fact is that any deviations may indicate serious problems in the body, including early detachment of the placenta, which is extremely unacceptable.

In some cases, it is not so easy to decrypt the received data. It is advisable to leave it to the doctors. Despite the fact that the indicators can fluctuate significantly during pregnancy, they should not go beyond acceptable limits. So, they have the following form: APTT - 17-20 s; Fibrinogen - up to 6.5 g / l; Lupus anticoagulant - should be absent; Platelets - 131-402 thousand / μl; Prothrombin - 78-142%; Thrombin time - 18-25 s; D-dimer - 33-726 ng / ml; Antithrombin III - 70-115%.

If the received data differs from these figures, appropriate measures must be taken. After all, all this can negatively affect the development of the fetus. Childbirth involves the loss of a small amount of blood. With poor coagulability, this is simply unacceptable. Therefore, the norm of the coagulogram must be observed.

The norm of the coagulogram in children

The norm of the coagulogram in children is practically no different from adult indicators. Thanks to this analysis it becomes possible to determine the ability of blood to rapidly coagulate. The procedure is performed in children not so often, mostly just before surgery.

In some cases, the analysis is done even with minor procedures. This will avoid all sorts of complications and make sure that the properties of platelets work to their fullest. Any deviations can lead to blockage of blood vessels. Often, a coagulogram is performed if there is a suspicion of the presence of blood pathologies.

Normally, the indicators should not go beyond the following limits: APTT - 17-20 s; Fibrinogen - up to 6.5 g / l; Lupus anticoagulant - should be absent; Platelets - 131-402 thousand / μl; Prothrombin - 78-142%; Thrombin time - 18-25 s; D-dimer - 33-726 ng / ml; Antithrombin III - 70-115%. Such data is considered standard. The norm of the coagulogram must fully comply with the declared indicators.

General information about the study

The hemostasis system consists of many biological substances and biochemical mechanisms that ensure the preservation of the liquid state of the blood, prevent and stop bleeding. It maintains a balance between clotting and anti-clotting factors. Significant violations of the compensatory mechanisms of hemostasis are manifested by the processes of hypercoagulation (excessive thrombosis) or hypocoagulation (bleeding), which can threaten the patient's life.

When tissues and blood vessels are damaged, plasma components (coagulation factors) participate in a cascade of biochemical reactions, resulting in the formation of a fibrin clot. There are internal and external pathways of blood coagulation, which differ in the mechanisms for triggering the coagulation process. The internal pathway is realized when blood components come into contact with the collagen of the subendothelium of the vessel wall. For this process coagulation factors XII, XI, IX and VII are required. The extrinsic pathway is triggered by tissue thromboplastin (factor III) released from damaged tissues and the vascular wall. Both mechanisms are closely interrelated and since the formation of the active factor X have common ways of implementation.

The coagulogram determines several key indicators hemostasis systems. Determination of PTI (prothrombin index) and INR (international normalized ratio) allows you to assess the state of the external pathway of blood coagulation. The IPT is calculated as the ratio of the standard prothrombin time (the clotting time of the control plasma after the addition of tissue thromboplastin) to the clotting time of the patient's plasma and is expressed as a percentage. INR is a standardized according to international recommendations prothrombin test. It is calculated by the formula: INR = (patient prothrombin time / control prothrombin time) x MIC, where MIC (international sensitivity index) is the thromboplastin sensitivity coefficient relative to the international standard. INR and IPT are inversely proportional, that is, an increase in INR corresponds to a decrease in IPT in a patient, and vice versa.

Studies of PTI (or a similar indicator - Quick prothrombin) and INR as part of a coagulogram help to identify disorders in the external and general blood coagulation pathways associated with a deficiency or defect in fibrinogen (factor I), prothrombin (factor II), factors V (proaccelerin) , VII (proconvertin), X (Stewart-Prower factor). With a decrease in their concentration in the blood, prothrombin time increases in relation to control laboratory parameters.

Plasma factors of the external coagulation pathway are synthesized in the liver. For the formation of prothrombin and some other coagulation factors, vitamin K is needed, the deficiency of which leads to disruption of the reaction cascade and prevents the formation of a blood clot. This fact is used in the treatment of patients with an increased risk of thromboembolism and cardiovascular complications. Thanks to the appointment of the indirect anticoagulant warfarin, vitamin K - dependent protein synthesis is suppressed. IPT (or Quick prothrombin) and INR in a coagulogram are used to monitor warfarin therapy in patients with thrombotic factors (eg, deep vein thrombosis, prosthetic valves, antiphospholipid syndrome).

In addition to prothrombin time and related indicators (INR, PTI, prothrombin according to Quick), other indicators of the hemostasis system can be determined in the coagulogram.

Activated partial thromboplastin time (APTT) characterizes the intrinsic pathway of blood coagulation. The duration of APTT depends on the level of high molecular weight kininogen, prekallikrein and coagulation factors XII, XI, VIII and is less sensitive to changes in the levels of factors X, V, prothrombin and fibrinogen. APTT is determined by the duration of blood clot formation after addition of calcium and partial thromboplastin to the blood sample. An increase in APTT is associated with an increased risk of bleeding, a decrease in thrombosis. This indicator is separately used to control therapy with direct anticoagulants (heparin).

Fibrinogen is a blood clotting factor I produced in the liver. Due to the action of the coagulation cascade and active plasma enzymes, it turns into fibrin, which is involved in the formation of a blood clot and thrombus. Fibrinogen deficiency can be primary (due to genetic disorders) or secondary (due to excessive consumption in biochemical reactions), which is manifested by impaired formation of a stable thrombus and increased bleeding.

Fibrinogen is also an acute phase protein, its concentration in the blood increases in diseases accompanied by tissue damage and inflammation. Determining the level of fibrinogen in the composition of the coagulogram is important in the diagnosis of diseases with increased bleeding or thrombosis, as well as for assessing the synthetic function of the liver and the risk of cardiovascular diseases with complications.

The anticoagulant system of the blood prevents the formation of an excess amount of active coagulation factors in the blood. Antithrombin III is the main natural inhibitor of blood coagulation, which is synthesized in the liver. It inhibits thrombin, activated factors IXa, Xa and XIIa. Heparin enhances the activity of antithrombin by 1000 times, being its cofactor. The proportional ratio of thrombin and antithrombin ensures the stability of the hemostasis system. With primary (congenital) or secondary (acquired) AT III deficiency, the blood coagulation process will not be stopped in a timely manner, which will lead to increased blood clotting and a high risk of thrombosis.

The formed thrombus undergoes fibrinolysis over time. D-dimer is a degradation product of fibrin, which makes it possible to assess the fibrinolytic activity of plasma. This indicator significantly increases in conditions accompanied by intravascular thrombosis. It is also used in the dynamic monitoring of the effectiveness of anticoagulant therapy.

What is research used for?

  • For a general assessment of the blood coagulation system.
  • For diagnosing disorders of the internal, external and general pathways of blood coagulation, as well as the activity of the anticoagulant and fibrinolytic systems.
  • For examination of the patient before surgery.
  • To diagnose the causes of miscarriage.
  • For the diagnosis of DIC, venous thrombosis, antiphospholipid syndrome, hemophilia and evaluation of the effectiveness of their treatment.
  • For monitoring anticoagulant therapy.

When is the study scheduled?

  • With suspicion of DIC, pulmonary embolism.
  • When planning invasive procedures (surgical interventions).
  • When examining patients with epistaxis, bleeding gums, blood in the stool or urine, hemorrhages under the skin and in large joints, chronic anemia, heavy menstrual flow, sudden loss of vision.
  • When examining a patient with thrombosis, thromboembolism.
  • With the detection of lupus antibodies and antibodies to cardiolipin.
  • With a hereditary predisposition to violations of the hemostasis system.
  • With a high risk of cardiovascular complications and thromboembolism.
  • With severe liver disease.
  • With repeated miscarriages.
  • When monitoring the hemostasis system against the background of long-term use of anticoagulants.

Today we will talk about a coagulogram - a blood test, the decoding of the indicators of which (APTT, PTI, INR and others) is a kind of propaedeutics of internal diseases, since, one way or another, the markers of this study are important in diagnosing and correcting almost any pathology. What is a kaogulogram of blood? Why does the doctor refer patients to this examination? What is included in the coagulogram and what is the interpretation of its indicators and what role does the blood coagulation factor play in our body? Today we will analyze in detail the list of markers that describe the quality of the plasma coagulation system, the complex of which, in fact, is a coagulogram.

What are blood clotting tests?

What is a coagulation test called? This study is called a blood test for a coagulogram. It should be noted that general study plasma also contains a coagulogram analysis that characterizes clotting. This, in particular, is the result of a blood test for platelets and clotting. A decrease in the number of platelets in relation to the standard value indicates certain problems. However, general analysis blood gives insufficient information to make a diagnosis, and the doctor prescribes to be checked for a coagulogram.

A blood coagulogram (analysis for a hemostasiogram, or a hemotest) is all the same. The analysis includes a set of indicators showing the quality of hemostasis, a mechanism that normally ensures the maintenance of a liquid state of the blood, and if tissues are damaged, stop bleeding or coagulation.

How to properly prepare for a coagulogram analysis

In order for the coagulation standards to be accurate, the analysis is taken on an empty stomach, in the morning. On the eve, 8-12 hours before plasma sampling, it is necessary to refuse food and sugary drinks. Alcohol and heavy meals should be stopped at least a day before. An hour before the procedure, it is highly advisable not to smoke, and also not to take active physical exertion and not be subjected to emotional stress. Immediately before donating blood for a coagulogram, you need to calm down and try to bring your heart rate (pulse) back to normal.

When treating with anticoagulants, a recent operation or blood transfusion, you need to inform the doctor about this so that the distorted norms of the blood test for the hemostasiogram *, which are possible against this background, are interpreted correctly. It is not necessary to take a blood test for a coagulogram * during acute periods chronic diseases and during a viral infection.

List of coagulogram indicators and their interpretation

Depending on the suspicions of the attending physician, you may be assigned a basic (small) coagulogram analysis or an extended one. As you may have guessed, the latter covers a wider range of blood clotting tests. Now let's talk about each of them in more detail.

So, what coagulation markers does the analysis of those included in the coagulogram contain? These are, in particular, indicators:

  • fibrinogen;
  • thrombin time;
  • prothrombin time;
  • Prothrombin index (PTI);
  • International normalized ratio;
  • APTT or APTT (activated partial (partial) thromboplastin time);
  • D-dimer;
  • Lupus anticoagulant screening;
  • Protein C;
  • Protein S;
  • Tolerance (sensitivity) of blood plasma to heparin;
  • Soluble fibrin monomer complex or SFMC;
  • Duration of bleeding according to Duke;
  • Blood clotting tests according to Lee White;
  • Antithrombin III;
  • Induced aggregation with ADP;
  • Induced aggregation with adrenaline.

Now let's start decoding:

1. Let's start with fibrinogen, which in essence is nothing more than a plasma protein, which is the basis of the blood coagulation system. The so-called factor I. It is formed in the liver and thrown into the blood when bleeding occurs or is threatened. A high level of fibrinogen in the blood may suggest an acute inflammatory process in the patient's body, tissue necrosis, heart attack, stroke, thyroid dysfunction (hypothyroidism), and cancer.

A reduced value of this marker is characteristic of severe liver damage, heart failure, promyelocytic leukemia, DIC.

2. The time during which fibrinogen is converted into a blood clot is called thrombin. The resulting clot is called fibrin and is based on a high molecular weight protein.

With a low thrombin time, there is a high risk of blood clots and clogging of blood vessels, and, conversely, a longer prothrombin time compared to the norm indicates a high risk of large blood loss in the event of bleeding, the name of the tendency to bleeding is hemosyndrome.

The slightest deviation of this indicator should be the reason for a more thorough study of other indicators.

3. Prothrombin time in the coagulogram shows the actual time of formation of a blood clot and is measured in seconds.

4. The previous indicator formed the basis for the calculation of such a blood marker as the prothrombin index (PTI), which is equal to the ratio of the norm value to that actually obtained as a result of the study. We will talk about the normative values ​​of PTI and other indicators characterizing the ability of our blood to coagulate later.

5. INR or international normalized ratio shows the body's response to one of the most studied and tested antithrombotic drugs - warfarin. Along with the use of this drug, strict control of the INR index of the blood is necessary. Its reference values ​​should not go beyond 2.0 to 3.0, since violation of the lower limit increases the risk ischemic stroke, and the top - hemorrhagic (that is, intracranial hemorrhage).

6. Standards APTT or APTT (activated partial (partial - from lat. Partial) thromboplastin time) reflects the time of blood clotting during a test involving clotting activators, which can be partial thromboplastin and calcium chloride. Thus, the APTT coagulogram indicates the effectiveness of coagulation factors in the coagulation process.

7. As a result of the breakdown of fibrin and as a result of this destruction of the thrombus, a product called D-dimer is formed. A blood test to determine this marker is carried out in order to exclude the risk of deep thrombosis. A positive D-dimer test value in a blood sample is an unfavorable prognostic factor for a patient with deep vein thrombosis of the lower extremities.

The results of this analysis for a coagulogram that exceed the standard value may indicate DIC, heart attack, the presence of blood clots in the veins and arteries, renal or hepatic insufficiency, inflammatory processes in the body, and severe histosis of pregnant women.

8. Lupus anticoagulant, screening. If lupus anticoagulants are detected as a result of the analysis of the hemostasiogram, we can talk about blood clots that block blood flow in almost any part of the body, which is extremely dangerous and can provoke such serious resolutions of the situation as a heart attack, pulmonary embolism, abortion, etc.

Lupus anticoagulants can be detected by a blood clotting test in people with AIDS, cancer patients, and those with an inflammatory process in their bodies.

9. Continuing to talk about the indicators of the coagulogram, let's focus on proteins C - proteins that slow down the time of blood clotting, thus preventing blockage of blood vessels and thrombosis. The main function of protein C is to provide optimal thrombosed mass. The lack of this protein is fraught with an increased risk of blood clots and is usually a factor that is inherited.

10. Enhances the properties of protein C protein S, thereby helping to slow down coagulation.

11. Plasma heparin tolerance indicates the time during which the blood coagulates from the moment of administration of heparin. A sharp jump in such time indicates that the indicator in question is less than normal. If the clot formation is slower or no changes are observed, then the plasma in the sample is considered tolerant (resistant) to the effects of heparin.

12. The RFMC coagulogram index or soluble fibrin monomeric complex shows how high the risk of thrombosis and embolism is (building up a blood clot in the lumen of the main vessel).

13. The Duke test is performed by piercing the tip of the finger or earlobe with a special Frank needle. The time during which the bleeding caused by this injection stops, in fact, is the value of this indicator of the coagulogram.

14. A blood test for coagulation according to Lee White is carried out in a special way. The difference lies in the speed of research. Very quickly, with a waxed syringe and sharp cannulas. The material is taken 1 ml into each of three special test tubes, which are heated up to 37 degrees. Blood clotting begins to occur from the moment the syringe plunger is pulled back when blood is drawn. This time is tracked. The sample tubes are tilted 50 degrees. The clotting process ends when the blood stops flowing when tilted.

If the blood on the coagulogram coagulates with a downward difference from the accepted norms, the patient can be assumed to have a disease such as hemophilia. This factor may also indicate the presence of liver damage, neoplasms in the bone marrow, malignant processes in the blood, obstructive jaundice, severe infectious diseases, burns. Heparin therapy and diathesis of newborns can also cause delayed blood clotting.

15. Antithrombin III is a protein designed to prevent venous thrombosis. Its function is to inhibit the activity of the main blood coagulation factors. Once in the bloodstream, antithrombin III binds to heparin, and this compound plays a key role in slowing down the clotting process.

In fact, this couple makes up about 80% of the blood coagulation system.

This test can show two types of deficiency of this protein - qualitative and quantitative. If the quantity factor is clear to us, then speaking of a qualitative lack of antithrombin, we mean its inability to cope with the inhibition of coagulation processes even in sufficient quantities.

16. Induced platelet aggregation with ADP (adesine triphosphate, which is a constituent of the vessel wall), what is it? Protecting the body from blood loss is a serious function of the body and platelets are very important in it. The ability of these cells to stick together (aggregate) among themselves and fix on the vessel wall at the site of damage at the initial stage of thrombus formation, allows you to stop bleeding.

The ability of platelets to form thrombi is determined by induced (forced) aggregation, that is, aggregation provoked by the introduction of certain substances into the body. In this case ADP.

17. The study of induced aggregation with adrenaline differs from the previous indicator with an inducer substance. As a rule, the assessment of platelet aggregation abilities is assessed in a complex way using ADP, collagen, adrenaline and ristomycin as inducers.

When is it prescribed to take a clotting test

So, a coagulogram or hemostasiogram is an analysis of blood coagulation and the duration of bleeding, and its results are used to diagnose a number of pathological processes and diseases. Such a factor as blood clotting plays an important role in the correction of conditions provoked by various disorders in the hemostasis system.

A blood coagulogram is mandatory prescribed for pregnant women, patients preparing for surgery, patients with heart attacks, strokes, and inflammatory processes. various genesis, liver disease, hemophilia. Control of blood clotting time (BCT) is necessary when taking anticoagulants to prevent thrombosis, as well as in many other cases.

Norms (reference values) of coagulogram indicators

  • Fibrinogen - 2–4 g/l;
  • Thrombin time - 15–18 seconds;
  • Prothrombin time - 10–13 seconds;
  • Prothrombin index (PTI) - 95–105%;
  • The international normalized ratio (INR) has several normative values, which depend on the reasons for the appointment of this examination: preoperative analysis - 0.85–1.25;
    • arfarin therapy for atrial fibrillation - 2.0–3.0;
    • treatment of pulmonary thromboembolism - 2.0–3.0;
    • situation after implantation of aortic and mitral valves- respectively 2.0–3.0 and 2.5–3.5;
    • in the presence of certain heart defects, a norm of 2.0–3.0 is recommended to prevent thromboembolism;
    • in the treatment of vein thrombosis and prevention of the formation of postoperative blood clots, an indicator equal to 2.0–3.0 is considered;
    • in the presence of vascular pathologies, infarction - 3.0–4.5.
  • APTT or APTT (activated partial (partial) thromboplastin time) - 30–40 seconds;
  • APTT is a particularly sensitive coagulation indicator;
  • D-dimer - no more than 250 ng/ml;
  • Lupus anticoagulant is characterized by the presence or absence in the blood;
  • Protein C - 70–130%;
  • The value of protein S, characterizing:
    • activity: total - 60–140%, free - 65–115%;
    • quantity: for men more than 70 U / l, for women more than 63 U / l.
  • Tolerance (sensitivity) of blood plasma to heparin - 8-10 minutes;
  • Soluble fibrin monomeric complex or RFMK - 3.36–4.0 mg per 100 ml of plasma;
  • Duke bleeding time - 2-3 minutes;
  • And Lee White's blood clotting time is 4–6 minutes;
  • Antithrombin III - 71–115%;
  • Induced aggregation with ADP - 30.7–77.7%;
  • Induced aggregation with adrenaline - 35–92.5%.

Propaedeutics of internal diseases in the blood coagulogram

Once on our site https: // site, the average person can only get acquainted with the indicators of such an extensive set of hemotests, which includes taking a blood test for coagulation (caogulogram or hemostasiogram). Each of the indicators described here has diagnostic significance in a certain set of blood tests, corresponding to the specific condition of individual patients. Only a doctor can interpret certain clotting markers that you will see on your coagulogram, and, moreover, make the correct diagnosis.

In contact with

To decipher the results of blood tests for coagulation with a coagulogram, you must be sufficiently qualified, but to understand the individual indicators of this test, the information below will be enough for you.

Blood sampling for coagulogram

FIBRINOGEN

Fibrin is necessary for the transformation of blood into a clot in order to be able to stop bleeding.

Testing for the presence of fibrinogen is carried out when it is necessary to provide for the behavior of the human body during a surgical operation, if inflammation is suspected, for improved diagnosis of vascular and heart disease.

Norms in g/l:

  • adults: 2 to 4;
  • babies under one year old: from 1.25 to 3;
  • newborns: 1.3 to 3;
  • children from one year: from 2 to 4;
  • women during pregnancy: about 6.

Due to an increase in plasma fibrinogen levels, heart attacks and strokes occur. It can be a catalyst for thyroid disorders and a harbinger of oncological problems.

A low level indicates a lack of vitamins B12 and C, liver problems, toxicosis in women during pregnancy, DIC. A decrease is possible with anabolic treatment, taking fish oil and exposing the body to snake venom.

Important! You can entrust the study of the results of analyzes only to specialists.

THROMBIN TIME (TV)

The time of transformation of fibrin into a thrombus, when exposed to calcium, is called thrombin.

The test is used in the following cases:

  • to determine the level of fibrinogen in plasma;
  • to understand the action of fibrinolytics in the treatment of the patient;
  • to confirm diagnoses of liver damage;
  • to detect miscarriage.
  • adults: 14 to 16 sec;
  • women in position: from 18 to 25 seconds;
  • infants: 13 to 17 sec;
  • premature newborns: 14 to 19 sec;
  • children under 14: 13 to 16 seconds;
  • teenagers: 12 to 16 sec.

Low values ​​can be caused by the appearance of blood clots, which can lead to blockage of blood vessels and death.

High values ​​confirm: autoimmune diseases, DIC in a patient, hereditary fibrinogen deficiency, vitamin K deficiency, use of anticoagulants in the treatment, infection of the body.

PROTHROMBIN TIME

The time it takes for a clot to form during plasma clotting is called prothrombin and is measured in seconds. The norm is considered to be readings in the range from 11 to 16 seconds, in the case of sampling from a pregnant woman, readings are considered normal, within 18 seconds.

This test is carried out during examination before surgery, to identify the general condition of the patient, in identifying anemia syndromes. In addition to these indications, a PTV test can be performed to confirm assumptions about the possibility of internal bleeding, identify liver pathologies, thrombosis, and other diseases.

Important! In medical laboratories, testing for PTV is carried out by various methods and only the attending physician with experience and sufficient qualifications can correctly interpret the results.

A decrease in PTT values ​​is observed during: pregnancy, taking aspirin, an increased content of red blood cells, thrombosis.

An increase in PTV readings gives reason to suspect: problems with coagulation, the presence of DIC, the use of warfarin, a lack of vitamin K, an excess of antithrombin. In addition, the use of antibiotics and hormonal agents can affect the increase in this indicator.

PROTHROMBIN INDEX

Its norm is from 95 to 105%, indications according to Quick are from 78 to 142%.

Low values ​​indicate: a lack of vitamin K, the patient is taking coagulants, liver damage, lack of fibrinogen, problems with blood clotting.

The indicators are exceeded: congenital deficiency of prothrombin and plasma Ac-globulin, acquired deficiency of blood coagulation, malfunctions of the liver, lack of vitamin K. In addition, an increase in indicators can be caused by the use of antibiotics and anabolics, hormonal drugs, aspirin.

ACTIVATED PARTIAL THROMBOPLASTIN TIME

Assign this type of study to confirm or refute the symptoms: heart attack, thrombosis, intestinal necrosis, thromboembolism, vascular damage. Bleeding, miscarriage, speculation, and DIC may also be a reason for testing.

The norm of APTT for adults is from 24 to 40 seconds, for babies just born from 25 to 43 seconds, for premature babies from 28 to 48 seconds.

Exceeding the norm shows a tendency to blood loss, but the background various diseases, and lowered APTT values ​​can confirm the lack of antihemophilic globulin, DIC in children.

A joint study of plasma with PTV allows the identification of the following problems:

  1. APTT is normal, PT is higher: lack of vitamin K, liver damage, poor blood clotting according to the function of factor VII;
  2. APTT is normal, PTT is normal, lupus anticoagulant is detected: diagnosis of von Willebrand's disease;
  3. APTT higher, PT higher: liver disease, lack of fibrinogen, lack of prothrombin;
  4. APTT is lower, PTT is normal: a decrease in blood clotting is possible.

Indications for D-dimer testing

With D-dimer without deviations, the version with thrombosis can be discarded. An increase in this marker indicates a high coagulability and a predisposition to the formation of blood clots.

LUPUUS ANTICOAGULANT

Separately, this marker is not allocated for research and is studied together with other markers in general tests.

PROTEIN C COAGULOGRAM PARAMETERS

Permissible values ​​of protein C in activity are from 70 to 130%, in quantitative terms more than 3 mg / ml or 60 nmol / l.

Assign research on this indicator with hereditary protein deficiency in close relatives, to confirm or refute other blood tests and if thrombosis is suspected.

PROTEINS S

PLASMA HEPARIN TOLERANCE

Excess normal indicators in 7-15 minutes indicates poor tolerance to heparin and possible diseases liver, and low rates can be triggered by oncological diseases, malfunctions of the heart, problems with blood vessels and pregnancy.

RFMK OR SOLUBLE FIBRIN-MONOMER COMPLEX

The RFMK indicator has normal values ​​from 3.36 to 4 mg / 100 ml.

Excess indicates thrombinmia, and indicators below the acceptable level most often occur when using anticoagulants.

DUKE BLEEDING TIME

This indicator is most often considered only in conjunction with others to get a more complete picture, and the stoppage of bleeding within 1.5 to 2 minutes is considered the norm.

LEE WHITE CLOUD

This test is carried out using glass or silicone tubes, and the results of the test, measured in minutes, are different for each type of tube. The norm for a glass test tube is from 4 to 7 minutes, and the norm for a silicone test tube is from 15 to 25 minutes.

Exceeding readings indicate possible problems with thyroid gland, severe blood loss or anaphylactic shock.

Deviation from the norm with a decrease in readings may indicate the use of anticoagulants, liver disease, severe infectious diseases,.

ANTITROMBIN III

This marker is measured when venous thrombosis is suspected, with negative sensitivity to heparin, and after surgery to remove a thrombus. Antithrombin III is also considered in conjunction with protein indications.

The following absolute numbers in % are considered acceptable:

  • for babies up to three days - 58-90;
  • over three days and up to one month - 60-89;
  • from one month to one year - 72-134;
  • from one year to six years - 95-134;
  • from six to eleven years old - 96-126;
  • over 16 years - 66-124.

Special indicators are calculated for women in position.

Exceeding the allowable values ​​can tell about a lack of vitamin K, common liver problems and suspicion of viral hepatitis, possible inflammation in the body, prolonged exposure to warfarin or phenylin therapy, PMS in women.

Indicators below the norm may indicate the predisposition of the body to the formation of blood clots, pregnancy in the last weeks. A decrease is also possible at the peak of PMS.

Attention! For correct decoding coagulogram, the doctor must have sufficient experience and qualifications.

Mistakes resulting from misinterpretation of results can lead to misdiagnosis and inappropriate treatment.