Deep vein Thrombosis (DVT): The dangerous blood clot

Jan 19, 2020 Dr Zulfikar Bux, Features / Columnists

By Dr Zulfikar Bux
Assistant Professor of Emergency Medicine

Our veins are responsible for returning blood to our heart for re-circulation. Disruption in this blood flow can lead to life threatening consequences and complications.
Deep Vein Thrombosis is one such condition that blocks flow of blood in our veins.
DVT occurs when a blood clot (thrombus) forms in one or more of the deep veins in your body, usually in your legs. One in every hundred persons with DVT will die from its complications.
Knowing who is at risk and how to detect a DVT can help you to access early treatment which can decrease your chances of having life threatening complications.

WHAT ARE THE SYMPTOMS OF A DVT?

A DVT in the leg may present with the following symptoms:
• Discoloration of the legs
• Calf or leg pain or tenderness
• Swelling of the leg or lower limb
• Warm skin
• Surface veins become more visible
• Leg fatigue
WHO’S AT RISK OF GETTING A DVT?
Many factors can increase your risk of developing deep vein thrombosis (DVT), and the more you have, the greater your risk. Risk factors for DVT include:
• Inheriting a blood-clotting disorder. Some people inherit a disorder that makes their blood clot more easily.
• Prolonged bed rest, such as during a long hospital stay, or paralysis. When your legs remain still for long periods, your calf muscles don’t contract to help blood circulate, which can increase the risk of blood clots.
• Injury or surgery. Injury to your veins or surgery can increase the risk of blood clots.
• Pregnancy. Pregnancy increases the pressure in the veins in your pelvis and legs. The risk of blood clots from pregnancy can continue for up to six weeks after you have your baby.
• Birth control pills or hormone replacement therapy. Birth control pills (oral contraceptives) and hormone replacement therapy both can increase your blood’s ability to clot.
• Being overweight or obese. Being overweight increases the pressure in the veins in your pelvis and legs.
• Smoking. Smoking affects blood clotting and circulation, which can increase your risk of DVT.
• Cancer. Some forms of cancer increase the amount of substances in your blood that cause your blood to clot.
• Heart failure. People with heart failure have a greater risk of DVT and pulmonary embolism. Because people with heart failure already have limited heart and lung function, the symptoms caused by even a small pulmonary embolism are more noticeable.
• A personal or family history of deep vein thrombosis or pulmonary embolism (PE). If you or someone in your family has had DVT or PE before, you’re more likely to develop DVT.
• Age. Being over age 60 increases your risk of DVT, though it can occur at any age.
• Sitting for long periods of time, such as when driving or flying. When your legs remain still for many hours, your calf muscles don’t contract, which normally helps blood circulate. Blood clots can form in the calves of your legs if your calf muscles aren’t moving for long periods.

HOW IS IT TREATED?

After DVT is diagnosed, the main treatment is medications that prevents your blood from clotting. Doctors may initially start you on anticlotting injections and send you home on anticlotting tablets once you have stabilized. You will probably take the tablets for at least 3 months. If anticoagulant medicines are not suitable, you may have a filter put into a large vein – the vena cava – in your abdomen. The filter traps and stops a blood clot travelling to your heart and lungs. A newer treatment involves breaking up and sucking out the clot through a small tube in the vein. You usually need to take anticoagulant medicine for several months after this treatment

WHAT LIFE-THREATENING COMPLICATION CAN OCCUR FROM A DVT?
Clots from DVT can break off and travel to your heart or lungs causing blockage. DVT patients are at risk of having a Pulmonary Embolism (lung blockage) and a heart attack (heart blockage). A person with DVT should monitor themselves for the following signs/symptoms which may indicate heart or lung blockage.
• Unexplained sudden onset of shortness of breath
• Chest pain or discomfort
• Feeling lightheaded or dizzy, or fainting
• Rapid pulse
• Coughing up blood

WHAT CAN YOU DO?
If you suspect that you or someone has a DVT, do not hesitate to visit a doctor. Your doctor will put you on blood thinning medications and monitor you over a prolonged period (6 months to a year) to ensure the clot is dissolving. Early detection and treatment is the key to decreasing complications of DVT. The more you know about DVT the better your chances of surviving an episode of this condition.