What are the risks of warfarin therapy. How does warfarin affect blood clotting. What are the symptoms of upper airway hematoma. How is upper airway hematoma diagnosed and treated. When should you seek medical attention for bruising while on blood thinners.

Understanding Warfarin and Its Effects on Blood Clotting

Warfarin is a commonly prescribed anticoagulant medication used to prevent blood clots in patients with various cardiovascular conditions. It works by interfering with the body’s vitamin K-dependent clotting factors, effectively “thinning” the blood and reducing its ability to form clots.

While warfarin therapy is crucial for many patients, it comes with potential side effects, including an increased risk of bleeding and bruising. One rare but serious complication is upper airway hematoma, which can be life-threatening if not recognized and treated promptly.

How does warfarin affect blood clotting?

Warfarin inhibits the production of vitamin K-dependent clotting factors in the liver. This leads to a prolonged clotting time, which is measured by the International Normalized Ratio (INR). Patients on warfarin require regular monitoring of their INR to ensure they are within the therapeutic range, as both under-anticoagulation and over-anticoagulation can have serious consequences.

The Link Between Warfarin and Bruising

Bruising is a common side effect of warfarin therapy. It occurs when small blood vessels under the skin break and leak blood into the surrounding tissues. Due to the anticoagulant effects of warfarin, these minor bleeds take longer to stop, resulting in more noticeable and extensive bruising.

Is bruising always a cause for concern in patients on warfarin?

While some degree of bruising is expected in patients taking warfarin, it’s essential to monitor the extent and frequency of bruising. Excessive or unexplained bruising may indicate that the warfarin dose needs adjustment or that there are underlying health issues that require attention.

• Minor bruising: Generally not a cause for concern
• Large, frequent, or spontaneous bruises: May require medical evaluation
• Bruising accompanied by other bleeding symptoms: Warrants immediate medical attention

Upper Airway Hematoma: A Rare but Serious Complication

Upper airway hematoma is an uncommon but potentially life-threatening complication of warfarin therapy. It involves bleeding into the soft tissues of the neck and throat, which can lead to airway obstruction if left untreated.

What are the signs and symptoms of upper airway hematoma?

Recognizing the symptoms of upper airway hematoma is crucial for early intervention. Patients and healthcare providers should be aware of the following warning signs:

• Neck swelling or pain
• Difficulty swallowing (dysphagia)
• Hoarseness or changes in voice
• Shortness of breath or difficulty breathing
• Bruising or discoloration of the neck area

If any of these symptoms occur in a patient taking warfarin, immediate medical attention should be sought to rule out upper airway hematoma.

Diagnosis and Management of Upper Airway Hematoma

Prompt diagnosis and appropriate management are essential in cases of suspected upper airway hematoma. Healthcare providers must be vigilant and consider this possibility in patients on warfarin presenting with neck swelling or respiratory symptoms.

How is upper airway hematoma diagnosed?

Diagnosis typically involves a combination of clinical assessment and imaging studies:

1. Physical examination: Evaluating neck swelling, bruising, and respiratory status
2. Laboratory tests: Checking INR levels and complete blood count
3. Imaging studies: CT scan or MRI of the neck to visualize the extent of the hematoma
4. Fiberoptic laryngoscopy: Direct visualization of the upper airway

What are the treatment options for upper airway hematoma?

Treatment approaches may vary depending on the severity of the hematoma and the patient’s clinical status:

• Reversal of anticoagulation: Administration of vitamin K, fresh frozen plasma, or prothrombin complex concentrate
• Airway management: Close monitoring, intubation, or tracheostomy in severe cases
• Conservative management: Observation and supportive care for mild cases
• Surgical intervention: Rarely needed, but may be necessary for large or expanding hematomas

Preventing Complications: Balancing Anticoagulation and Safety

While warfarin remains an essential medication for many patients, its use requires careful management to minimize the risk of complications such as upper airway hematoma.

How can patients reduce their risk of warfarin-related complications?

Patients taking warfarin can take several steps to reduce their risk of bleeding complications:

• Adhere to prescribed dosage and follow-up appointments
• Maintain consistent vitamin K intake through diet
• Inform all healthcare providers about warfarin use
• Avoid activities with a high risk of injury
• Be aware of potential drug interactions
• Monitor for signs of bleeding and report concerns promptly

Alternative Anticoagulation Options: Beyond Warfarin

In recent years, new oral anticoagulants (NOACs) have emerged as alternatives to warfarin for some patients. These medications, such as apixaban, rivaroxaban, and dabigatran, offer potential advantages in terms of dosing and monitoring requirements.

Are NOACs safer than warfarin in terms of bleeding risk?

While NOACs generally have a lower risk of intracranial hemorrhage compared to warfarin, they still carry a risk of bleeding complications. The choice between warfarin and NOACs depends on various factors, including:

• Patient’s specific medical condition
• Kidney function
• Cost and insurance coverage
• Patient preference and lifestyle factors

Healthcare providers must carefully weigh the pros and cons of each anticoagulation option for individual patients.

The Importance of Patient Education and Monitoring

Effective management of warfarin therapy requires a collaborative effort between healthcare providers and patients. Education plays a crucial role in ensuring safe and effective anticoagulation.

What key information should patients on warfarin understand?

Patients taking warfarin should be educated on the following aspects of their treatment:

• The reason for anticoagulation and its importance
• Proper dosing and administration of warfarin
• The significance of regular INR monitoring
• Potential side effects and warning signs of complications
• Dietary considerations and vitamin K intake
• Drug interactions and over-the-counter medication precautions
• When and how to seek medical attention for bleeding concerns

By empowering patients with knowledge, healthcare providers can improve adherence to therapy and reduce the risk of complications such as upper airway hematoma.

Future Directions in Anticoagulation Management

As medical research advances, new approaches to anticoagulation management are being explored. These developments aim to enhance the safety and efficacy of blood thinning therapies while minimizing the risk of complications like upper airway hematoma.

What emerging technologies show promise in anticoagulation management?

Several innovative approaches are being investigated to improve anticoagulation therapy:

• Point-of-care INR testing devices for home monitoring
• Pharmacogenetic testing to guide warfarin dosing
• Novel reversal agents for NOACs
• Artificial intelligence algorithms for predicting bleeding risk
• Wearable devices for continuous monitoring of coagulation status

These advancements hold the potential to revolutionize anticoagulation management, potentially reducing the incidence of complications like upper airway hematoma while improving overall patient outcomes.

In conclusion, while upper airway hematoma remains a rare but serious complication of warfarin therapy, awareness, prompt recognition, and appropriate management are key to preventing adverse outcomes. As anticoagulation practices continue to evolve, the balance between effective therapy and patient safety remains a primary focus for healthcare providers and researchers alike.

Is bruising a side effect of blood thinners?

A reader asks: “My wife recently had a lot of bruising on her leg. Can bruises be caused by blood thinners? How do you know whether it’s something more serious?”

Senior Cardiac Nurse, Chloe MacArthur, says:

Blood thinners (anticoagulants such as warfarin, or antiplatelets  such as aspirin or clopidogrel) are taken by many people with heart and circulatory conditions. They interrupt the body’s clotting process, to help reduce the risk of clots which could cause a stroke or heart attack. This can mean that you are more likely to get bruising.

Bruises happen when the smallest blood vessels under the skin (capillaries) break and start to leak, causing discolouration. Blood thinners are designed to slow down the blood clotting, so the broken blood vessels take longer to stop leaking, which can lead to a worse bruise or bruising more easily.

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For most people taking these blood thinners, this is very manageable and isn’t something you need to worry about. If you notice more bruises after you start taking a blood thinner, there’s a good chance that the two are related. But bruising may not be caused by blood thinners, other illnesses or some vitamin deficiencies can also cause bruising.

If you’re worried about the bruising, or if you’re experiencing other new symptoms (including other signs of bleeding, such as nosebleeds or bleeding gums), speak to your GP or specialist. You may need your blood thinner dose changed, or you may need to try a different medication. And if you are worried that your bruising is caused by something else, they will be able to reassure you or refer you for more tests.

Can I get help with paying my prescription?

Medical prescriptions are free in Northern Ireland, Scotland and Wales. They are also free for people in England who meet certain criteria, including people who are:

• under 16 or over 60
• receiving Income Support, JSA, ESA or Universal Credit
• pregnant
• 16-18 and in full-time education
• and/or have certain health conditions, including a continuing disability or diabetes that can’t be controlled with diet.

If you aren’t entitled to free prescriptions for your medicines you might be able to save money by buying a Prescription Prepayment Certificate (PPC). 

getting help with prescription costs.

Meet the expert

Chloe MacArthur is a Senior Cardiac Nurse at the British Heart Foundation. 

Published September 2022

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What are blood thinners?

Blood thinners are medicines that prevent blood clots from forming. They do not break up clots that you already have. But they can stop those clots from getting bigger. It’s important to treat blood clots, because clots in your blood vessels and heart can cause heart attacks, strokes, and blockages.

Who needs blood thinners?

You may need a blood thinner if you have:

• Certain heart or blood vessel diseases
• An abnormal heart rhythm called atrial fibrillation
• A heart valve replacement
• A risk of blood clots after surgery
• Congenital heart defects

What are the different types of blood thinners?

There are different types of blood thinners:

• Anticoagulants, such as heparin or warfarin (also called Coumadin), slow down your body’s process of making clots.
• Antiplatelets, such as aspirin and clopidogrel, prevent blood cells called platelets from clumping together to form a clot. Antiplatelets are mainly taken by people who have had a heart attack or stroke.

How can I take blood thinners safely?

When you take a blood thinner, follow the directions carefully. Blood thinners may interact with certain foods, medicines, vitamins, and alcohol. Make sure that your health care provider knows all of the medicines and supplements you are using.

You may need regular blood tests to check how well your blood is clotting. It is important to make sure that you’re taking enough medicine to prevent clots, but not so much that it causes bleeding.

What are the side effects of blood thinners?

Bleeding is the most common side effect of blood thinners. They can also cause an upset stomach, nausea, and diarrhea.

Other possible side effects can depend on which type of blood thinner that you are taking.

Call your provider if you have any sign of serious bleeding, such as:

• Menstrual bleeding that is much heavier than normal
• Red or brown urine
• Bowel movements that are red or black
• Bleeding from the gums or nose that does not stop quickly
• Vomit that is brown or bright red
• Coughing up something red
• Severe pain, such as a headache or stomachache
• Unusual bruising
• A cut that does not stop bleeding
• A serious fall or bump on the head
• Dizziness or weakness

• Anticoagulants

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• Blood Thinner Pills: Your Guide to Using Them Safely

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• ClinicalTrials. gov: Anticoagulants

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Experience in the treatment of bleeding and recurrence of venous thromboembolic complications that developed during therapy with vitamin K antagonists

Anticoagulant therapy (ACT) is widely used for the treatment and prevention of venous thromboembolic complications (VTEC), which represent a serious socio-economic problem. The associated high mortality rates necessitate the long-term use of anticoagulants [1-6].

To achieve long-term hypocoagulation, oral indirect anticoagulants of the vitamin K antagonist (VKA) group are considered the drugs of choice, among which warfarin is most often used. Depending on the clinical situation, the duration of warfarin therapy ranges from 3 months to 1 year, and in some cases warfarin is prescribed for life [1, 2, 7].

Despite the use of known dosing and efficacy monitoring algorithms, long-term warfarin therapy can lead to hemorrhagic complications and recurrent VTEC [7, 8].

The incidence of major, including fatal, bleeding ranges from 0.4 to 7.2% per year. Minor bleeding occurs in more than 15% of patients per year [9]. The risk of bleeding correlates with the value of the international normalized ratio (INR). Thus, with an increase in INR from 3.5 to 4.5, the risk of bleeding increases by 20 times, and with an INR of more than 7.5, by 40 times [10]. In most cases, developed hemorrhagic complications lead the patient to a general surgical hospital.

The risk of rethrombosis directly on the background of warfarin therapy ranges from 4.5 to 16% per year, while it is highest during the first 2-3 weeks from the start of therapy [7]. After cessation of therapy with indirect anticoagulants, the risk of relapse increases again and reaches a maximum during the first 6 months, after which it gradually decreases. The frequency of rethrombosis after discontinuation of warfarin therapy reaches 20% per year [11].

The aim of our study was to analyze the results of treatment of patients with relapses of VTEC and hemorrhagic complications that developed during warfarin therapy.

We conducted a retrospective analysis of data on the treatment of patients with complications of prolonged warfarin therapy. We used materials from a traveling hematology team of the Hematological Research Center of the Ministry of Health of Russia and a surgical clinic from February 2011 to December 2015. The study included 116 patients (68 men and 48 women) with surgical complications of prolonged warfarin therapy. The average age of men was 62.3±10.4 years, women – 53.3±9.6 years. Among the treated patients, men over 60 years of age predominated, including patients, regardless of gender, over 70 years of age (27.6%) and over 80 years of age (23.3%).

32 patients took warfarin for a long time for deep vein thrombosis of the lower extremities, and 84 for various cardiac pathologies. At the same time, 10 patients were diagnosed with repeated VTEC against this background, and 106 patients had hemorrhagic complications of different localization and intensity.

The duration of taking warfarin in patients varied. Only 8 (6.9%) patients included in the study took warfarin for less than one year, most patients used it for more than a year, while almost half of the patients (48.1%) took warfarin for more than 5 years.

Examination of patients included clinical, instrumental and laboratory research methods. The state of the hemostasis system was monitored using standard laboratory parameters (activated partial thromboplastin time, INR, D-dimer level and prothrombin complex parameters) and global tests (thromboelastography — TEG and thrombodynamics).

Statistical processing was carried out using the Biostat 4.03 program, and the statistical package Statistica for Windows 8.0 was also used. Data are presented as mean values ​​with standard deviation.

The distribution of patients depending on the initial pathology that caused the appointment of anticoagulant therapy, and the nature of the developed complication is presented in Table. 1. Table 1. Distribution of patients (n=116)

VTEC recurrence occurred in 10 patients. In all cases, venous thrombosis was detected, in 6 patients – proximal, in 4 – distal localization. Floating nature of thrombosis was detected in 7 patients.

In all cases, we considered a decrease in the patient’s dose of the drug and/or lack of adequate laboratory control as the likely cause of relapse. Only 3 patients in the group were taking warfarin at the recommended therapeutic dose. Seven patients were taking warfarin at a dose less than recommended. According to standard laboratory tests, 6 patients were in a state of hypocoagulation at the time of admission to the hospital, and 4 were in normocoagulation. For a more detailed assessment of the state of the hemostasis system, we used global coagulation tests.

The thrombodynamic test revealed a state of hypocoagulation (warfarin therapy was effective) only in 2 patients, while the rest showed normo- and hypercoagulability. In 3 patients with hypercoagulability, confirmed by a thrombodynamic test, the level of D-dimer was increased. Our previous studies have shown that the combination of these two factors can be regarded as a state of increased thrombotic readiness (high risk of developing VTEC) [12]. Thromboelastography turned out to be less sensitive to determining the state of hypercoagulability and confirmed the results of standard laboratory studies – only in one patient, according to this test, a state of hypercoagulation was revealed and in 2 – a state of hypocoagulation, in the remaining patients normocoagulation was observed.

All 10 patients diagnosed with recurrent VTE were treated with unfractionated or low molecular weight heparin followed by resumption of warfarin. Only in 2 patients, the development of embolic thrombosis was an absolute indication for surgical prophylaxis of PE. For the rest of the patients, treatment was limited to correction of anticoagulant therapy.

Bleeding was most frequently reported in cardiac patients treated with warfarin for cardiac arrhythmias (55, 51.9%).

In 67 patients, only conservative agents were used. 27 patients were operated on (25 on an emergency basis, 2 2 days after admission). Another 20 patients underwent endoscopic hemostasis for gastrointestinal bleeding. Two patients underwent puncture of a hematoma of the leg under ultrasound control.

Depending on the characteristics of the clinical picture and approaches to treatment, all patients with hemorrhagic complications were divided into three groups (Table 2). Table 2. Division of patients with bleeding by groups and principles of treatment (n=106) Note. * – in the work with the consent of the patients, a drug that was not registered in the Russian Federation was used, PDA – prothrombin complex concentrate, FFP – fresh frozen plasma.

The most numerous (49 patients) was the 1st group of patients who had minor bleeding (soft tissue hematomas, epistaxis and hematuria) or no bleeding at the time of admission, but there was a high risk of its development. There were no indications for surgical treatment in this group of patients (Fig. 1). Rice. Fig. 1. Hematoma of soft tissues of both lower extremities while taking VKA in patient B. a — general view; b — view of the posterior surface of the lower leg.

The mean value of INR in the 1st group was the highest — ≥9.5±3.3. Warfarin was discontinued in all patients of this group upon admission until the INR normalized.

According to international recommendations, in patients taking warfarin for a long time, an increase in the INR index of more than 3. 0 with the simultaneous development of hemorrhagic syndrome should be regarded as warfarin-associated coagulopathy [13]. Minor bleeding (subcutaneous hematomas, hematuria, epistaxis, etc.) against the background of INR ≥4.5, as well as the presence or absence of hemorrhagic syndrome with INR ≥7.0 (high risk of bleeding) served as an indication for the appointment of intravenous vitamin K In our study, there were 17 such patients (2 patients with INR over 4.5 and minor hemorrhagic syndrome, 15 with INR over 7.0 and the absence or presence of minor hemorrhagic syndrome). Some patients of this group were transferred to the surgical department from other departments of the hospital with high INR numbers and a history of low bleeding. To normalize hemostasis, they were additionally prescribed vitamin K ₁ (phytomenadione) at a dose of 10 mg 2 times a day intravenously for the first 2-3 days. The remaining 32 patients managed to eliminate severe hypocoagulation by discontinuing warfarin. In most patients, the decrease in the INR to the therapeutic level occurred within 5-7 days.

Performed global tests confirmed the state of severe hypocoagulation in all patients, while only TEG reflected the severity of coagulopathy, which was determined by the prolongation of the clot formation time.

The use of vitamin K in standard doses made it possible to quickly reduce the INR values ​​to the required therapeutic parameters without the use of additional funds, which made it possible to use it as monotherapy in patients with minor manifestations of hemorrhagic syndrome, as well as in patients with an overdose of warfarin and a high risk of spontaneous bleeding. When the INR reached the therapeutic range, vitamin K was canceled.

The 2nd group included 32 patients in whom clinically significant bleeding occurred and stopped before hospitalization, but at admission there was a high risk of its resumption. The consequences of bleeding in this group were different, which required the division of patients into two subgroups according to further treatment tactics.

In 18 patients, upon admission to the hospital, bleeding stopped, but there was a high probability of its resumption, i.e., there were no indications for emergency surgical treatment (subgroup 1). 10 patients were diagnosed with ongoing gastrointestinal bleeding and 8 patients with uterine bleeding. The mean INR was 5.8±1.9therefore warfarin was discontinued in all patients until INR normalized.

Along with endoscopic hemostasis, all patients in this subgroup received intravenous infusion of vitamin K at a dose of 10 mg twice a day for 1–2 days. To normalize hemostasis, taking into account the volume of blood loss, transfusion of fresh frozen plasma was performed in parallel at a dose of 15–20 ml/kg (300–400 ml on average), recommended by Russian and international standards [14]. If necessary, FFP transfusion was repeated the next day. After reaching therapeutic values ​​of INR, 5 patients resumed anticoagulant therapy with warfarin at a dose of 5 mg per day under the control of INR, the other 5 patients were transferred to other oral anticoagulants.

The 2nd subgroup included 14 patients who did not have active bleeding at admission, but were diagnosed with hematomas of various sizes and localization. Ultrasound and computed tomography revealed retroperitoneal hematomas in 4 patients, there were no signs of intra-abdominal bleeding. Patients were treated conservatively. In 10 patients, during the examination, strained hematomas of the lower leg were verified (Fig. 2). 2. Ultrasound scan. Intermuscular hematoma of the leg. which led to the development of compression syndrome, the so-called sheath syndrome.

Mean INR in this subgroup was 5.6±0.27. Warfarin was discontinued in all patients upon admission to the hospital. At the same time, all patients had indications for intravenous infusion of vitamin K, which was carried out in a volume of 10 mg 2 times a day for 30-40 minutes. Patients with retroperitoneal hematomas, along with intravenous administration of vitamin K, were transfused with individually calculated doses of FFP, averaging 300–400 ml/day.

Taking into account the nature of clinical symptoms, 6 patients underwent emergency opening and drainage of leg hematomas under endotracheal anesthesia. In 4 patients with tense leg hematomas, but moderately severe pain and ischemic syndrome against the background of hemostasis correction, hematoma puncture was performed under echo control. Two patients underwent opening and drainage of hematomas due to the ineffectiveness of the puncture performed under endotracheal anesthesia.

When INR ≥2.0 was reached, all patients were resumed anticoagulant therapy with LMWH at prophylactic doses, followed by the transfer of 2 patients to warfarin at a dose of 5 mg per day under the control of INR and 2 patients to direct oral anticoagulants (dabigatran, rivaroxaban).

Combination therapy with FFP and vitamin K proved to be quite effective in patients who are in a state of severe hypocoagulation (INR 5.8±1.9) and at risk of complications requiring surgical intervention. The use of such a combination of drugs allows in a short time (on average, after 60 – 63.4 ± 4.8 min) to achieve a decrease in INR to therapeutic values ​​and reduce the risk of active bleeding, which makes it possible to perform surgical operations with minimal risk.

The 3rd group included 25 patients who continued to bleed on the background of long-term use of warfarin at the time of admission. Pulmonary and uterine bleeding, bleeding from various parts of the gastrointestinal tract, as well as bleeding from the retroperitoneal space, which led to the formation of retroperitoneal hematomas, were identified. This situation required intensive care and urgent surgical control of bleeding. Examination of patients in this group revealed high values ​​of INR (7.5±2.5), which made it difficult to stop bleeding.

Taking into account the need for quick decision-making and correction of detected coagulopathy, only TEG was used from global tests in group 3 patients, which made it possible not only to confirm hypocoagulation, but also to assess the severity of coagulopathy in each patient and select an individual treatment regimen. The thrombodynamic test required a long time (from 40 min to 1 h) and had low sensitivity to hypocoagulable conditions [1, 12].

Active bleeding in this group of patients, severe hypocoagulation, and indications for emergency surgical control of bleeding made it impossible to use only the combination of FFP and vitamin K. Large doses of FFP are needed to quickly restore clotting factors, and vitamin K, in turn, provided a slow decrease in the effect of blockers of vitamin synthesis K. In addition, the content of clotting factors in FFP is not standardized, and during long-term storage in any form, their content in plasma decreases on average by another 25% [15]. In accordance with international standards, the use of CPC is recommended in this situation.

MDA infusion was carried out with the help of protroplex 600 (Baxter, Austria), which contains in a proportional ratio procoagulants: 4 vitamin K-dependent coagulation factors (II, VII, IX, X) and natural anticoagulants: protein C, antithrombin III and a small dose of heparin, which prevents the activation of clotting factors during the preparation of the solution before administration to the patient. The dose of the drug was determined according to the initial INR, according to Japanese researchers [16-18], with an initial level of INR ≥4.5, the recommended dose of COC is 1000-1200 IU, with INR <4.5 - 500-600 IU of COC. Ten patients were infused with COC at a dose of 600 IU, the rest - at a dose of 1200 IU. Patients of the 3rd group did not need repeated infusions of COC. The hemostatic effect of COC developed rapidly - 15 minutes after injection, due to the high concentration of the main coagulation factors: in 1 ml of COC it is 25-30 times higher than in 1 ml of FFP. After the introduction of the PDA, the bleeding was stopped in all patients and the repeated administration of the drug was not required. No rebleeding was recorded before the patients were discharged from the hospital.

Thirteen operated patients of this group were prescribed MDA infusion after determining the INR and TEG, which was performed directly in the operating room. It was TEG, based on the prolongation of the activation time for clot formation, that determined the severity of coagulopathy in a patient and made it possible to control the normalization of the coagulation system after the introduction of COC. The rapid development of the hemostatic effect made it possible to successfully perform surgical hemostasis in all patients of the 3rd group. In all cases, the decision on the nature and extent of hemostatic therapy and the choice of the timing of surgical intervention was made with the participation of a specialized mobile team of anesthesiologists-resuscitators of the Hematological Research Center of the Ministry of Health of Russia.

Thus, prolonged warfarin therapy may be accompanied by the development of bleeding and recurrence of VTE. In all 116 examined patients, complications of prolonged warfarin therapy occurred at the outpatient stage of treatment and were associated with a violation of the dosing regimen of the drug and inadequate control over its effectiveness, as well as often with low adherence of patients to prescriptions.

Standard laboratory parameters do not always adequately assess the effectiveness of warfarin therapy. For an accurate assessment of the causes of the development of complications, in addition to clinical and instrumental methods of examination, it is necessary to study the patient’s hemostasis system. For this purpose, in addition to standard laboratory parameters, global tests (TEG and thrombodynamics test) are used. It is preferable to use the thrombodynamic test in patients with repeated VTEC, and the TEG in patients with hemorrhagic complications.

Adequate treatment of hemorrhagic complications that occur against the background of prolonged warfarin therapy is possible only if the developing warfarin-associated coagulopathy is corrected simultaneously.

The choice of treatment regimens for patients with surgical complications of prolonged warfarin therapy should be based on an assessment of both clinical and instrumental data from the examination of patients, and the state of their hemostasis.

Therapeutic measures in the group of patients with repeated VTEC in most cases can be limited by adjusting the dose of warfarin, and in patients with hemorrhagic complications against the background of severe hypocoagulation, the elimination of warfarin-associated coagulopathy is required.

Patients with high INR, high risk of spontaneous bleeding, and no indication for surgical treatment require vitamin K monotherapy against the background of temporary withdrawal of warfarin.

In the treatment (including surgery) of patients with clinically significant bleeding on the background of warfarin coagulopathy, it is required to combine intravenous infusion of vitamin K with the administration of one or more doses of FFP. Elimination of warfarin-associated coagulopathy with FFP without vitamin K infusions is reasonable only for non-severe bleeding in patients with initially low INR levels.

Achieving good results in surgical treatment of ongoing bleeding against the background of warfarin-associated coagulopathy provides a combination of a complex of hemostatic measures, including intravenous administration of vitamin K, FFP and single, and if necessary, double administration of COC.

The absence of deaths and complications in both groups of patients with surgical complications of prolonged warfarin therapy proves the adequacy of the developed treatment algorithm for this category of patients.