Deep vein thrombosis

Posted on 12 September 2013

It’s widely reported on in the media, but do you know the facts about deep vein thrombosis (DVT)? Vascular surgeon Professor Thanyani Mulaudzi (MBChB, FCS, Cert Vasc Surg, MMED (Surg)), from the Mediclinic Heart Hospital in Pretoria, gives some clarity on blood clots and DVT.

What is it that causes blood clots and deep vein thrombosis?
Deep vein thrombosis (DVT) can occur in any section of the venous (vein) system, but it commonly involves the deep (not superficial) veins of the lower limbs. Three factors contribute to the development of venous thrombosis (i.e. a blood clot in the vein): slow blood flow (blood-flow stasis), damage to the blood vessel walls and blood-clotting abnormalities. These three are referred to medically as Virchow’s triad. DVT presents a clinical challenge. A doctor would need to establish risk factors for the development of DVT in a patient, as these impact on the treatment. To consider would be things like previous incidents of DVT, immobilisation, pregnancy, certain medication and blood-clotting abnormalities.

I’m going on a long-haul flight. How worried should I be?
Prolonged inactivity can slow the circulation and promote blood -low stasis. This is a real concern for those taking long flights. The risk of DVT can be counteracted by taking fluids and regular walks while flying in the plane.

If I get a blood clot, what’s the worst-case scenario?
Usually, DVT first presents itself as a swollen limb. But with proper treatment, very few patients will have complications related to this disease. The life-threatening complication, though, is a massive pulmonary embolism (known as PE, when a huge blood clot breaks and travels to the lungs). It can cause sudden death. If DVT turns to PE, you will have difficulty in breathing and chest pain.

If I experience this, what treatment will I be given?
If you are a patient with significant DVT, you’ll be admitted to hospital, where your lower limbs will be elevated. You’d be put on anticoagulant lower-molecular weight heparin medication (LMWH) for few days. Treatment with warfarin would continue for three to six months, depending on your risk factors for DVT. (Patients with recurrent DVT are given warfarin for life.) If a patient goes on from DVT to develop PE, the treatment is the same as above, but those with severe symptoms will be managed in the critical care unit. Here, the pulmonary emboli needs to be removed urgently, either by thrombolysis (medication that dissolves the clot) or a thrombectomy (an operation to remove the clot). Very few patients, those who have contra-indications to heparin or have complications related to heparin, may need to have an inferior vena cave (ICV) filter device inserted in the inferior vena cava of the heart, to prevent a massive pulmonary emboli.

So what can I do to prevent getting blood clots and DVT?
Be active. Patients who are to have surgery need to guard against DVT with prophylaxis, like early mobilisation after the operation, the pneumatic compression of the lower limbs or anticoagulation medication to prevent clot formation. The treating doctor will decide on which type of prophylaxis based on the patient’s risk for DVT.

If you have questions on this post, or any other medical matter, please visit us on Facebook.

The information provided in this article was correct at the time of publishing. At Mediclinic we endeavour to provide our patients and readers with accurate and reliable information, which is why we continually review and update our content. However, due to the dynamic nature of clinical information and medicine, some information may from time to time become outdated prior to revision.