What Is Venous Thromboembolism?
Venous thromboembolism is a serious and often underdiagnosed condition but can be prevented in most conditions when intervened at the right time. Deep vein thrombosis is a medical condition that occurs when a clot is formed in the deep vein. The usual site of the clot developing is in the lower legs, thighs, or pelvis. In some cases, the condition can even occur in the arms.
What Are the Signs and Symptoms of Venous Thromboembolism?
Most of people suffering from deep vein thrombosis do not show any symptoms. Some of the signs and symptoms of deep vein thrombosis are:
-
Swelling.
-
Pain.
-
Tenderness.
-
Redness of the skin.
If one has any of these symptoms, consult a doctor as soon as possible.
How Is Venous Thromboembolism Diagnosed?
The diagnosis of venous thromboembolism is made through special tests. They are discussed below:
-
Duplex Ultrasound - This is an imaging test that uses sound waves to see the blood flow in the vein. Also, it can detect any block or clot in the deep veins. It is the standard imaging test done to diagnose deep vein thromboembolism.
-
D-Dimer Blood Test - It is a blood test done to measure a substance that is released in the blood when a blot breaks up. When the D-dimer test is negative, it means that the patient did not have any blood clots.
-
Contrast Venography - This is a special type of x-ray that uses contrast material (dye). The dye is injected into the large vein in the foot or ankle, through which the doctor can see veins in the leg and the hip. Contrast venography is the most accurate test in diagnosing blood clots. But the disadvantage is that it is an invasive procedure. So this test is majorly replaced by duplex ultrasonography and is done in only very few patients.
-
Magnetic Resonance Imaging (MRI) - This test uses a magnetic field and radio waves to provide images of the required part of the body.
-
Computed Tomography (CT) Scan - A CT scan can be done to diagnose this condition.
What Is Venous Thromboembolism Prophylaxis?
There are methods adopted to prevent the occurrence of venous thromboembolism during surgical procedures. Prophylaxis using mechanical methods which will increase the venous return from the legs along with thrombolytic drugs is most effective to prevent morbidity and mortality in such patients. Even though there is various evidence to support the use of thromboprophylaxis, this is underused by surgeons as they believe that the risk of thromboembolism is not enough to justify the risk of potential hemorrhage by using anticoagulants. The risk of thromboembolism will depend upon the type of patient and the type of surgery that is performed.
How Is Venous Thromboembolism Prophylaxis Done?
There are various intervention methods for the prophylaxis of venous thromboembolism and they include graduated compression stockings (GCS), intermittent pneumatic compression (IPC) devices, and pharmacologic agents like unfractionated heparin, low-molecular-weight heparin, and fondaparinux. Most of the cases use a combination of mechanical methods along with pharmacologic agents. Each of these methods is discussed below:
1. Mechanical Devices-
-
Graduated Compression Stockings - They work by compressing the deep and superficial venous system, which will increase the velocity of the blood flowing in the venous system and will also help to empty the venous cusp vales. There are two types: knee-high and thigh-high.
-
Intermittent Pneumatic Compression Devices- The external pressure is applied in a sequenced manner which will thereby increase the pulsatile venous blood flow. This will improve the emptying of the veins and thus decreases the venous pressure which will increase the arterial flow. The forces applied by the intermittent compression devices will lead to shear and strain forces on the endothelial cells which will enhance the antithrombotic, profibrinolytic, and vasodilatory effects. There are different types of intermittent compression devices, and they are: graduated sequential compression devices which will produce sequential compression from proximal to distal, and uniform compression devices, which will produce uniform compression. Both these types are effective in decreasing the risk of venous thromboembolism.
2. Pharmacological Agents- Low molecular weight heparins and low dose unfractionated heparin are the pharmacological agents that are used to prevent venous thromboembolism.
How Is Venous Thromboembolism Treated?
1. Anticoagulants - These are the medications that are used to treat venous thromboembolism. They decrease the ability of the blood to form clots. They also prevent the clot from getting larger as they are absorbed by the body.
Injectable coagulants are:
-
Unfractionated Heparin (injected into a vein).
-
Low molecular weight heparin (injected under the skin).
-
Fondaparinux (injected under the skin).
Anticoagulants that are taken orally are:
-
Warfarin.
-
Dabigatran.
-
Rivaroxaban.
-
Apixaban.
-
Edoxaban.
These anticoagulants also increase the chances of bleeding, so they should be monitored regularly to prevent any unusual bleeding.
2. Thrombolytics- These are medications that dissolve the clot formed. Also, they have a higher risk of causing bleeding compared to anticoagulants. So they are given in severe cases only.
3. Inferior Vena Cava Filter- These are filters that are inserted in the inferior vena cava. This is used when the anticoagulants cannot be used or they do not work well. The filters that are introduced will capture the clot before it reaches the lungs.
4. Thrombectomy or Embolectomy - This is the surgical method for removing the clot. This is not very often used when compared to other methods. Thrombectomy is done to remove the clot from a patient with deep vein thrombosis, and embolectomy is done to remove the clots from the lungs.
What Are the Complications of Venous Thromboembolism?
The most serious complication of venous thrombosis is that the clit gets dislodged from its original location and travels to the lungs through the blood, causing pulmonary embolism. If the clot is small, then it can be treated, and the patient will recover from it. However, if the clot is large, then it can even be fatal. A percentage of people who have venous thromboembolism can suffer from post-thrombotic syndrome, which is a long-term complication from the damage caused to the valves in the veins. These people can have swelling, pain, discoloration, and scaling or ulcers in the affected part of the body.
Conclusion
The prevention of venous thromboembolism post-surgery is an important part of the recovery after the surgery. There are various techniques to prevent it. One must follow the instructions given by the healthcare workers after the surgery properly in order to avoid any complications.
