The Dangers Of Deep Vein Thrombosis (DVT).
DVT - Deep Vein Thrombosis
This is a common problem with many people and unfortunately can lead to a life-threatening situation. A basic definition of a Deep Vein Thrombosis - nearly always abbreviated to DVT - is:
"A clot that forms in one of the deep veins of the body - usually the legs or pelvis area."
Medical Dictionary Online
This straigntforward definition hides the fact that a DVT has the potential to lead to much more serious conditions. However, we'll first of all look at how and why a thrombosis (blood clot) may form in a deep vein and then why this condition can be so dangerous.
Why DVT's develop
A Deep Vein Thrombosis (DVT) may also be called a venous thrombosis, but the terms mean exactly the same thing.
There might not be a clear cause of why a DVT develops with some people. Medically they usually develop due to:
- Having blood that clots too easily
- Damaged blood vessels
- Having a slow blood flow.
There are also risk factors that are believed to increase the chance of developing a clot:
- Lack of activity - basically if you are a couch potato then you have an increased chance of developing a DVT. Walking, running and any form of exercise that increases the circulation through the legs is an excellent way to prevent a blood clot forming. When blood becomes stagnant due to weak or damaged blood vessels this increases the chances of the blood forming a clot.
- Family history - with many medical conditions it's believed that if a member of your family has suffered from a particular condition then genetically you might also be at risk from the same condition.
- Obesity - being overweight, especially when reaching the levels of clinical obesity, can cause many serious conditions to develop including DVT's. This is because obesity makes the heart work harder in order that blood can be circulated to the extra fat layers. This leads to high blood pressure that damages blood vessels so increasing the chances of a blockage in those vessels.
- Age - as we get older obviously our circulation and blood vessels are not as in good condition as they used to be. In addition, our mobility may become restricted due to other disorders.This can lead to further weakness and damage in blood vessels so increasing the risk of blood clots forming.
- Smoking restricts the blood vessels, therefore increases the chances of clots forming inside them.
In addition to the life style and social causes above, you can be at further risk from developing a DVT if:
- You are a patient in hospital. This is because the majority of people who are admitted to hospital are not only inactive for long periods of time, but the condition that they are admitted for may give them an additional risk of forming a clot. For example after surgery, it may seem as if nurses are being hard when they get patients out of bed soon after an operation, however, this is to prevent DVT's and other complications such as pneumonia setting in. Your risk of developing a DVT will be assessed on admission and preventative treatment given such as anti-coagulants or compression stockings. Anti-coagulants prevent blood from clotting and compression stockings increases the circulation through the legs.
- Blood vessel damage - if you already have blood vessel damage due to a previous injury, varicose veins, some medications, vein inflammation can all make you more prone to developing blood clots.
- Medical conditions and treatments - a number of these,for various reasons, can increase the chance of forming a blood clot, especially a DVT. These include - some forms of cancer, chemotherapy, heart/lung disease, stroke, rheumatoid arthritis, certain blood conditions/diseases.
- In addition, pregnancy, some types of contraceptive pill - such as the combined pill - and HRT treatment are known to increase the risk of blood clots.
As mentioned before, there are some people who will not experience any symptoms at all with a DVT. However, for most the following are the most common:
- Normally only one leg is affected but a DVT can occur in both.
- People complain of aching and of their leg feeling heavy.
- The area where the clot has formed is warm to the touch and red. This red area usually appears at the back of the leg, below the knee.
- People may experience pain at the back of the leg. Frequently when the foot is bent upward towards the knee, this makes the pain worse.
If these signs appear then you should speak to a doctor as soon as possible. DVT's can be treated but the the danger lies with the medical emergencies that may arise from it.
Medical complications of DVT
There are a number of complications that may arise from a DVT. However, there are two in particular that develop most often:
- Pulmonary Embolism
- Post-thrombotic Syndrome
This is by far the most serious of DVT complications. As we know a DVT is a blood clot usually in the leg. What can happen is that a part of this clot may break off and starts to travel in the blood stream. This piece of clot can end up entering one of the lungs and becoming lodged in one of the smaller blood vessels - this is called a pulmonary embolism.
Pulmonary is a medical term that relates to the lungs and the blood flow through the lungs. An embolism is any foreign body, including a blood clot, that gets stuck while travelling in the blood stream.
With a pulmonary embolism the symptoms depend on the size of the clot:
- Small clot - this might not cause any symptoms.
- Medium clot - usually breathing difficulties with chest pain are experienced.
- Large clot - can cause the lungs to collapse, which leads to heart failure.
NHS UK have found that about one in ten people who develop an untreated DVT will have a pulmonary embolism through a medium or large clot. Therefore, if you have any concerns or experience any of the symptoms described earlier, then go and get a check up from your doctor.
The main signs of a pulmonary embolism are:
- Cough - this can be a non-productive dry cough or the coughing might produce blood and/or blood and mucous.
- Feeling light-headed/dizzy, some people also pass out.
- Chest pain - the pain usually feels very sharp, stabbing and is often made worse when you breath in.
- Breathlessness - people often feel short of breath and this may come on suddenly or build up gradually.
- People - for obvious reasons - may feel very anxious. They may also be sweating heavily.
If you have any of these symptoms you must seek medical attention immediately.
Treatment for a pulmonary embolism is anti-coagulant medication. Warfarin is one of the best known for this. Warfarin may also be given as a preventative treatment prior to surgery and other hospital procedures. Anti-coagulants not only prevent the blood from clotting, but with medicines like warfarin, they also break the clots down. However, there is a risk of internal bleeding with warfarin, so blood tests have to be carried out regularly to ensure that the clotting ability of blood is not reduced too far.
Warfarin or a similar drug may also be used to treat a DVT. Other treatments for DVT/blood clots include thrombolysis which is a chemical that destroys blood clots and is given by injection. However, not everyone is suitable to have this form of treatment. Surgery can also be performed to remove the clot - especially if there is a risk of gangrene - but this is only usually carried out as a last resort.
This is a long-term condition that sometimes occurs and usually happens to people who have had a history of DVTs.
When a clot forms in one vein, the blood is diverted to other veins in order that the blood can continue to move as normally as possible. However, this can put too much pressure on other veins and the surrounding tissues start to become affected. This can lead to a rash, pain in the calf area of the leg, swelling and ulcers also develop. This condition only usually occurs to people who are overweight and have had a DVT more than once in the same leg.
As with any condition, prevention is always better than a cure. Keeping reasonably fit and your weight within normal limits are two of the best ways to prevent clots forming. However, if you do find that some of the symptoms described are developing, then speak to your doctor. Don't ignore the problem - it won't go away on it's own and the earlier a clot is discovered the easier and quicker the treatment.