The hemostasis system is a complex physiological process that acts as an “emergency service.” It keeps blood in a liquid state, ensuring that it flows freely through the vessels. When a person is injured, a blood clot is instantly formed to stop the bleeding. If this balance is disturbed, deadly risks are possible – blood clots form that can block a pulmonary artery, cause a stroke or heart attack, or cause uncontrolled bleeding. A coagulogram – a blood clotting test – can help assess the functioning of the hemostasis system and prevent complications.
The article is relevant for those who are preparing for surgery, planning a pregnancy, taking blood-thinning medications, or want to understand the tests prescribed by a doctor. We will answer the question "what is a coagulogram", understand how to decipher the test results, and find out why the norms for children and pregnant women differ from the usual ones.
What kind of analysis is a coagulogram?
Coagulogram – what is it? It is a comprehensive laboratory analysis , a blood clotting test, that evaluates the functioning of the hemostasis system. It shows how quickly and effectively the blood clots.
Hemostasis is a complex system that consists of two stages:- Primary (platelet) hemostasis. Platelets (blood platelets) are the first to "congregate" at the site of an "accident", sticking together and forming a primary protective barrier.
- Secondary (plasma or coagulation) hemostasis. A special protein, fibrinogen (a blood clotting factor), attaches to platelets, forming a strong mesh that secures the primary plug.
Doctors prescribe a coagulogram to monitor both levels of homeostasis and check for a weak link in this complex pipeline that could lead to sudden thrombosis or prolonged bleeding during surgery.
What is included in a blood coagulogram?
Depending on the medical task, laboratories conduct a basic or extended panel of tests.
Basic coagulogram indicators – a standard set that includes:- PT (Prothrombin Time) / INR (International Normalized Ratio). Estimates the blood clotting time during primary hemostasis. The normal PT is 11-16 seconds, the normal INR is 0.8-1.1. This indicator is especially important when taking warfarin.
- APTT (Activated Partial Thromboplastin Time). Shows the effectiveness of secondary homeostasis. The normal APTT is 24–36 seconds. This indicator is used when a patient receives heparin.
- Fibrinogen. This is the basis for a future blood clot. The norm of fibrinogen is 2.0–4.0 g/l. The amount of protein increases during inflammation and pregnancy.
- Thrombin time (TT). Evaluates the final stage of clotting – the rate of conversion of fibrinogen to fibrin. Normal – 14-21 seconds.
- D-dimer. A marker of blood clot breakdown. The norm is less than 0.5 μg/ml. An increased concentration may indicate blood clotting disorders and serious diseases that are accompanied by the formation of blood clots.
- Antithrombin III and protein C. These are natural anticoagulants ("blood thinners") that prevent excessive blood clot formation. The norm of antithrombin is 80-100%, protein C is 70-140%. With a deficiency of anticoagulants, the risk of thrombophilia increases significantly.
- Coagulation factors (II, V, VII, VIII, IX, X, XI, XII). Normal range is 50–150%. Prescribed when hemophilia and other genetic diseases are suspected.
Coagulogram: norm and deviations
| Indicator | Coagulogram indicators - the norm for adults | What does promotion mean? | What does decrease mean? |
|---|---|---|---|
| ATC | 25-35 seconds | Bleeding tendency | Tendency to thrombosis |
| PTC | 11-15 seconds | Slowing down clotting | Accelerated clotting, risk of thrombosis |
| EOM | 0.85-1.15 | Too thin blood, which threatens bleeding | Blood is excessively thick, indicating a risk of thrombosis |
| Fibrinogen | 2.0-4.0 g/l | Inflammation, infections, pregnancy, heart attack, stroke | Hereditary deficiency, severe liver disease, DIC syndrome |
| Thrombin time | 14-21 seconds | Liver failure | High fibrinogen levels |
| D-dimer | <0.5 μg/ml | Thrombosis, pulmonary embolism (PE), DIC, pregnancy, cancer | No clinical significance |
There are 2 types of deviations from the norm of the coagulogram: hypercoagulability and hypocoagulability.
Hypercoagulability is a condition of “thick blood” due to overactive hemostasis. Risks: deep vein thrombosis, pulmonary embolism (PE), stroke, heart attack, pregnancy complications.
Hypocoagulation is a condition of “thin blood” caused by slow clotting. Risks: prolonged bleeding even from small cuts, hematomas from minor injuries, internal bleeding, bleeding gums and nosebleeds, menorrhagia (heavy menstrual bleeding), complications after surgeries and injuries.
Important! It is strictly forbidden to self-diagnose and select medications to thin or thicken the blood. A doctor should interpret the coagulogram and prescribe treatment, taking into account the history and existing symptoms.
When is a coagulogram prescribed?
The main indications for a coagulogram:- Suspicion of thrombosis or pulmonary embolism (PE). The presence of pathology may be indicated by swelling and pain in one leg, sudden shortness of breath, chest pain.
- Bleeding. The doctor will recommend a test if you have frequent nosebleeds, bleeding gums, or heavy menstruation.
- Preoperative screening. It is imperative to have a test done before surgery (even before wisdom tooth extraction) to avoid a situation where the patient bleeds on the operating table.
- Treatment control. Taking anticoagulants (Heparin, Warfarin, Apixaban, Xalerto, Eliquis) or antiplatelet drugs (aspirin).
- Liver pathologies (hepatitis, cirrhosis). It is in the liver that most blood clotting factors are synthesized.
- Autoimmune diseases: Systemic lupus erythematosus and antiphospholipid syndrome (APS) can trigger thrombosis.
When to take a coagulogram for preventive purposes? The analysis is recommended for people from risk groups: with hereditary coagulopathy (hemophilia, von Willebrand disease), varicose veins, severe cardiovascular diseases in history. It should also be taken periodically if close relatives have been diagnosed with strokes or heart attacks.
How to properly prepare for the analysis
The hemostasis system is extremely sensitive to external stimuli. Therefore, proper preparation for a coagulogram is essential for the accuracy of the result, which includes:- Withdrawal of medications. It is imperative to inform your doctor about all medications you are taking. With his or her approval, some medications (especially anticoagulants or antiplatelet agents) will need to be skipped or taken after blood sampling.
- Fasting for 8-10 hours. The coagulogram is taken on an empty stomach, preferably in the morning (from 8 to 11 a.m.). During the fast, it is allowed to drink clean, non-carbonated water.
- Avoid alcohol. Do not drink alcoholic beverages for 48 hours before the test, as they affect coagulation.
- Avoiding physical exertion. The day before the analysis, refrain from intense training and heavy work.
Arrive at the clinic earlier than the specified time. It is advisable to sit quietly for 10–15 minutes before taking the coagulogram to normalize blood circulation.
Factors affecting the analysis result
Sometimes there are cases when a person feels fine, but the tests show terrible results. Therefore, it is worth knowing what affects the coagulogram.
The results of the study may change under the influence of various factors:- Medications. Anticoagulants (warfarin, apixaban, dabigatran, heparin) and antiplatelet drugs (aspirin, ibuprofen, clopidogrel), which thin the blood, significantly affect the test results. Hormonal contraceptives can increase hypercoagulation.
- Nutrition. Green vegetables (cabbage, broccoli) and spinach contain vitamin K, which accelerates blood clotting.
- Stress and exercise. Stress increases adrenaline levels, which constrict blood vessels and activate platelets, causing temporary hypercoagulation. Blood clotting also increases with excessive exercise.
- Chronic diseases. Cirrhosis, hepatitis, liver failure, nephrotic syndrome, systemic inflammatory diseases, and cancer can affect the test results.
- Preanalytical stage errors. If blood is delivered to the laboratory for a long time, stored incorrectly, or collected with too fine a needle, hemolysis (destruction of red blood cells) occurs, resulting in inadequate results.
Results may vary between laboratories due to the use of different equipment, reagents, and methods. Therefore, monitoring of performance over time should be done in the same laboratory.
Coagulogram is an important study that allows you to assess the functioning of the blood coagulation system in children and timely identify possible risks of bleeding or thrombosis. In childhood, indicators may vary depending on the age and condition of the body, so the correct interpretation of the results is especially important. For high-quality diagnostics and consultation with a pediatrician, contact the Mamyn Dim polyclinic - we will help you understand the results and, if necessary, prescribe further examinations
Coagulogram during pregnancy
During pregnancy, a woman's body prepares for the upcoming birth and inevitable blood loss. Therefore, the hemostasis system goes into "high alert" mode - the level of fibrinogen increases (especially in the third trimester), the activity of clotting factors increases, the content of D-dimer increases, and the concentration of antithrombin decreases.
A coagulogram is usually ordered three times during pregnancy: at registration, at 20–22 and 30–32 weeks. If there are concomitant problems, the analysis is performed more often. It is especially important to donate blood for testing 2–4 weeks before the expected date of delivery to assess the risk of hemorrhage and prevent complications.
When conducting a coagulogram for pregnant women, the fibrinogen level increases to 5.0–6.0 g/l (normal level is 4.0). D-dimer also increases significantly during pregnancy – its level can exceed the norm by 2–3 times. This is completely normal and does not indicate thrombosis. But if PE is suspected, additional diagnostics are required: duplex ultrasound, CT.
Uncontrolled hypercoagulation in pregnant women can lead to the development of serious complications: thrombosis, preeclampsia, DIC syndrome. DIC syndrome (disseminated intravascular coagulation) is especially dangerous, in which massive uncontrolled bleeding begins. Regular coagulograms help doctors keep risks under control.
Coagulogram in children
The hemostasis system in children is in the process of development. Therefore, the coagulogram in children differs for different age categories:- Newborns (0–7 days) – low levels of clotting factors, high tendency to hemorrhage.
- Infants (7 days – 1 year) – the concentration of clotting factors gradually increases, the norms slowly approach adult values.
- Children 1–18 years old – most indicators are similar to adult norms, but slight differences are possible.
- chronic nosebleeds;
- bleeding gums;
- prolonged menstrual bleeding in teenage girls;
- frequent causeless appearance of bruises on the body;
- suspicion of hereditary coagulopathy (if there were cases of hemophilia or von Willebrand disease in the family);
- preparation for operations (for example, removal of adenoids, tonsils);
- the need to monitor hemostasis after severe diseases (sepsis, DIC syndrome).
Coagulogram norms in children by age group are shown in the table.
| Indicators | Newborns (0–7 days) | Babies (7 days – 1 year) | Toddlers from 1 to 5 years old | Children from 6 to 11 years old | Teenagers from 12 to 18 years old |
|---|---|---|---|---|---|
| PTC (sec) | 12–21 | 11–18 | 11–16 | 11–15 | 11–14 |
| AHTC (sec) | 30–90 | 30–40 | 27–40 | 25–38 | 25–37 |
| Fibrinogen (g/l) | 1.5–3.0 | 1.5–3.0 | 2.0–3.5 | 2.0–4.0 | 2.0–4.0 |
How to prepare a child for a coagulogram? You should not force your baby to starve for 8 hours. For infants, blood donation is allowed 2–3 hours after the last feeding. For older children, it is enough to wait 4–6 hours. The main thing is to minimize stress, because a child’s crying and panic can greatly distort the results.
Practical tips:- Talk to your child in advance and explain why they need to donate blood.
- Don't lie to your child, don't say that "you won't feel anything." Say honestly: "It will be a little unpleasant, like a mosquito bite, but very quickly."
- Bring a favorite toy with you, hug your child during the procedure,
- Distract your baby with conversations or videos on your phone right at the time of the injection.
- After the procedure, be sure to praise the child for his courage and reward him with a nice bonus (buying a new toy, going to the play area).
Where to take a coagulogram?
The Mamyn Dim polyclinic invites you to take a coagulogram in Kharkiv. We have created comfortable conditions for children and adults, and our own modern laboratory guarantees high accuracy of the analysis without pre-analytical errors and quick results. The medical staff of our laboratories have experience working with children and use techniques that make the process as less traumatic as possible.
To donate blood for coagulation, make an appointment in advance and choose a convenient time using the online form. Our doctors will help you correctly interpret the results and, if necessary, give recommendations for further examination or prescribe the most effective therapy.