Treatment of venous thromboembolism (VTE)

The prompt diagnosis and treatment of a blood clot is important. Deep vein thrombosis (DVT) and pulmonary embolism (PE) are treated with drugs called anticoagulants (sometimes referred to as ‘blood thinners’), which interact with the clotting process in the blood and reduce the blood’s tendency to clot [1]. As anticoagulants help to stop blood clots from getting larger and reduce the risk of other clots developing, it is important to know that the risk of bleeding is greater and that a wound may take longer to heal.

For DVT, anticoagulants reduce the risk of an embolus travelling to the lungs and causing a PE. With anticoagulant treatment, existing clots usually dissolve and disappear over time [1]. Effective anticoagulation is important to reduce the long-term side effects of DVT and PE, particularly recurrence and the risk of post-thrombotic syndrome [2].

Anticoagulants

Anticoagulants are the most common treatment for VTE and are given either as a tablet or an injection [2, 3]. Patients with a clot are treated with either one or two anticoagulants [2].

Most often, anticoagulation requires two drugs, and patients are given injections and tablets every day for about one week [2]. A test called ‘INR’ is used to measure how well the anticoagulant drugs are working. During the initial treatment, injections and tablets are taken together until the INR is 2.5. When the INR reaches this level, the injections are stopped and the patient continues taking tablets. The INR value should stay within the range of 2–3 during treatment, and is monitored by regular blood testing [2]. The dose of the tablet is increased or decreased to ensure the correct range is maintained. This is important to reduce the risk of too much or too little anticoagulation [2].

Recently, doctors have started to prescribe tablets to treat VTE that do not require injections at the start of treatment [3]. These tablets are given at high doses for several weeks at the start of treatment, followed by a lower dose until treatment end [3].

In most cases, patients with DVT are treated as outpatients and hospital admission is not required [2]. In some cases of uncomplicated PE, outpatient treatment is also possible. However, PE is a serious medical condition and often a patient will be admitted to hospital to start the anticoagulant treatment. The duration of anticoagulation depends on the circumstances that led to the development of the DVT or PE. If a patient has a temporary risk factor, for example recent bed rest because of injury or illness, treatment may last 3 to 6 months. If the risk factor is persistent, such as thrombophilia, or the doctor believes there is an increased risk for recurrent clots, anticoagulation might be prescribed indefinitely [2].

Compression stockings (also called graduated compression stockings) are often prescribed after a DVT [1]. They are used to reduce the chronic swelling that can occur after a DVT and may help to prevent long-term side effects of DVT such as post-thrombotic syndrome.

Compression stockings

Other treatments for VTE

Thrombolytics are a type of drug used in selected cases to dissolve blood clots and may be given by using a catheter, a long, slender tube that is inserted into the vein to deliver the clot-dissolving drug [1].

Occasionally, a small filter called an inferior vena cava filter is inserted into a large vein in the groin or neck, that is intended to catch clots as they move through the body to the lungs to help prevent PE occurring [1].

References

  1. Cleveland Clinic. Deep Vein Thrombosis (DVT). Accessed 6 November 2018
  2. Chapman NH et al. Venous thromboembolism: Management in general practice. Australian Family Physician 2009; 38: 36-40.
  3. Brieger D & Curnow J. Anticoagulation: a GP primer on the new oral anticoagulants. Australian Family Physician 2014; 43: 254-9.