Sudden leg swelling, watch out for blood clots
The main causes of leg swelling, also known as lower limb edema, are: 1) lower limb lymphedema; 2) lower limb varicose veins; 4) lower limb deep vein insufficiency; 5) lower limb deep vein thrombosis; 6) cardiac, liver and kidney insufficiency; 7) infection, etc. When edema appears in the lower limbs, we should identify them one by one, and the most important one is to determine whether the leg swelling is due to lower limb thrombosis.
Deep vein thrombosis in the lower extremities is mainly caused by damage to the vein wall, blood hypercoagulation and blood rheology changes. Vein is the channel of blood return, after thrombosis, the thrombus blocks the channel, blood cannot return, but can only hoard in the lower limbs, resulting in swelling of the lower limbs. At the same time, thrombus in the vein can also form phlebitis, which aggravates the swelling and pain of the affected limb. It is not difficult to distinguish whether a swollen leg is caused by a blood clot, and the diagnosis can be confirmed by ultrasound Doppler examination of the veins of the lower extremities.
When lower limb vein thrombosis is diagnosed, the affected limb should never be massaged, because the venous blood will enter the lungs to complete the oxygen exchange after returning to the heart, and massaging and squeezing the lower limb will easily dislodge the thrombus, which will flow through the heart with the blood flow and finally “stuck” in the pulmonary artery, resulting in the obstruction of pulmonary artery blood flow, causing symptoms such as coughing, chest tightness, and even This is the medical term of pulmonary embolism. According to statistics, more than 60% of pulmonary embolism is caused by deep vein thrombosis in the lower extremities, and the serious and fatal pulmonary embolism accounts for about 1% to 5%. Therefore, when sudden swelling of the lower limbs is found, bed rest should be taken immediately, avoid strenuous exercise as much as possible, and pay special attention not to massage the affected limbs. Once coughing, chest tightness and difficulty in breathing appear, you should be alert to whether pulmonary embolism has occurred and should be sent to hospital immediately for emergency treatment.
Rely on ultrasound for definite diagnosis
As mentioned above, the fastest and non-invasive way to identify the cause of lower limb swelling, determine whether there is a blood clot, and initially determine the location of the clot is deep vein color Doppler ultrasound. In addition to the presence or absence of thrombus in the veins, ultrasonography can also provide information about the diameter of the veins in the lower extremities, the blood flow, the speed and direction of the blood flow, and the functional status of the valves in the lower extremities, which has a high diagnostic value for venous diseases in the lower extremities. Some hospitals use venography, which also has some diagnostic value. Venous ultrasound examination is now more popular and is generally available at hospitals above the county level.
Anticoagulation and thrombolysis to unblock blood vessels
If you have lower extremity venous thrombosis, the best treatment is anticoagulation and thrombolysis. Generally speaking, the effect of thrombolysis is better for fresh thrombus, and the effect of thrombolysis is worse for old thrombus. Fresh thrombosis refers to thrombosis within two weeks of onset, but when the thrombosis becomes old and tightly adhered to the vessel wall, the effect of thrombolysis will not be too good. There are two methods of thrombolytic therapy: one is systemic thrombolysis, i.e., thrombolytic drug is injected into the body through the vein, and the drug will be distributed throughout the body to dissolve the thrombus gradually; the other is local thrombolysis through the catheter, i.e., the catheter is placed into the thrombus through the interventional method, and the thrombolytic drug is injected locally through the catheter to achieve the purpose of thrombolysis. The main advantage of systemic thrombolysis is that it is convenient and non-invasive, and it can treat the thrombus in the lower extremity and the thrombus that has been dislodged to the pulmonary artery at the same time; the disadvantage is that it requires a larger dose of thrombolytic drug and the concentration of the drug in the thrombus is low, so the effect of thrombolysis is slow. The advantages of catheter thrombolysis are that the thrombolytic effect is relatively good, the drug dose required is relatively low, and the thrombolysis speed is relatively fast; however, the disadvantages are also obvious, such as trauma, complications, dislodgement of thrombus due to intravascular operation, relatively high cost, complicated operation, and the need for special equipment, etc. It is difficult to perform this treatment in general hospitals at the district and county level.
Not all patients can undergo thrombolysis, for example, those with coagulation dysfunction, those who are allergic to thrombolytic drugs, those who have had cerebrovascular accidents or traumatic brain injury within six months, and those who have undergone cranio-cerebral surgery are not suitable for thrombolysis.
In addition to anticoagulation and thrombolysis, a few patients also need surgical thrombus retrieval treatment. Because of the high chance of recurrence of thrombosis after surgery, not all patients with lower extremity venous thrombosis can undergo surgical thrombus removal. So, in what cases is surgery necessary? In a few cases of thrombosis, all the large and small veins of the affected limb are blocked and the venous return is completely terminated, resulting in a high degree of swelling of the affected limb and compression of the arteries of the affected limb, making the arterial blood supply impaired and the affected limb appearing ischemic and hypoxic and purple. At this time, the affected limb is cold and in severe pain, which we clinically call “femoral cyanosis” or “femoral blue swelling”. At this time, the affected limb may be on the verge of necrosis, so timely surgery should be performed to remove the thrombus, eliminate the swelling, restore blood flow, release the arterial compression, and relieve the condition.
After lower limb thrombosis is diagnosed, the main treatment methods are thrombolysis and anticoagulation. Thrombolysis mainly includes catheter and systemic intravenous drug thrombolysis, and our hospital mainly uses intravenous systemic anticoagulation and thrombolysis, and treats more than 800 patients with deep vein thrombosis every year, with remarkable efficacy and hospitalization time of about two weeks. The risk of bleeding due to underdose or overdose. If necessary, elastic stockings should be worn to prevent swelling of the lower extremities and the resulting pathologies, such as post-thrombotic syndrome. The term “post-thrombotic syndrome” refers to the inability to prevent blood from flowing backwards in the veins of the lower extremities (the veins of the lower extremities flow from the bottom to the top) due to impaired venous reflux, or the impairment of the function of the deep vein valves caused by the thrombosis. The venous blood will accumulate in the calf for a long time, and the nutrition of the calf skin will be impaired, and over time, varicose veins, darkening and darkening, itching and repeated infections will appear in the calf. In serious cases, there are incurable skin ulcers, which we often call “old rotten legs”.
In short, leg swelling should not be underestimated, it may be your deep vein “traffic jam”, which will not only cause leg swelling and pain, but also may lead to prolonged and unhealed “old rotten leg”, which may even be life-threatening, so it should be paid great attention to everyone!
Removing the cause Prevention is important
Since many thrombosis cannot be completely cured, prevention of thrombosis is especially important. To prevent thrombosis, we must first know what kind of people are vulnerable to venous thrombosis.
The classical theory is that damage to the vessel wall, slow blood flow and increased blood concentration are the three main factors that cause venous thrombosis. Many venous thrombosis originates from slow-flowing areas, such as gastrocnemius plexus and venous pockets, etc. Clinically, it is found that patients with braked limbs or long-term bed-ridden patients are prone to form venous thrombosis, all of which suggest that slow blood flow is one of the factors of thrombosis. In addition, the following factors may be the triggering factors of thrombosis.
1, age deep vein thrombosis can be seen in people of any age, but statistics show that the incidence increases gradually with age, and the incidence of 80-year-old people is more than 30 times that of 30-year-old people. Older people have higher activity of coagulation factors in the blood, and the stagnation of venous blood in the calf muscle is heavier, so the incidence is higher than that of younger people.
2.Braking We commonly see that patients who are bedridden for a long time are prone to thrombosis. During long-distance car or airplane travel, lower limb activity is reduced, the contractile effect of calf muscles is reduced, and venous blood return is significantly slowed down, thus increasing the risk of thrombosis.
3, history of venous thrombosis About 25% of patients with acute thrombosis have previous history of venous thrombosis, and these newly formed thrombi often come from the original lesion of the veins.
4, malignant tumor about 19%-30% of DVT patients combined with malignant tumor, the main reason is that malignant tumor release pro-coagulant substances, improve the activity of blood clotting factors.
The high incidence of post-surgical thrombosis shows that surgery is an important predisposing factor for thrombosis, and the patient’s age, type of surgery, trauma size, surgery time and post-operative bed time all affect the occurrence of thrombosis.
6.Trauma The blood is in a high coagulation state after trauma, which will lead to the easy formation of thrombosis.
7.The incidence of postpartum deep vein thrombosis is higher after delivery, which is closely related to the hypercoagulable state of blood after delivery. Postpartum hypercoagulable state can make the placenta in the uterus after the abruption can be quickly stop bleeding in a short period of time, not to develop postpartum hemorrhage, but in turn may lead to the occurrence of thrombosis.
8, oral contraceptives Studies show that women of childbearing age taking contraceptives are 8 times more likely to have thrombosis than those not using contraceptives.
9, central venous cannulation Clinical central venous cannulation more and more, making the incidence of thrombosis also increased, especially in the upper extremity of the thrombosis of 65% of patients with central venous cannulation related. Venous cannulation not only damages the vessel wall, but also tends to form thrombosis on the surface of the cannula.
10, other diabetes, hyperlipidemia, obesity, varicose veins of lower extremities and cardiac insufficiency are still debated whether they are susceptibility factors of thrombosis, they may not be independent susceptibility factors, but these patients are susceptible to thrombosis, which may be related to other susceptibility factors.
Among the above-mentioned thrombosis predisposing factors, most of them are the change of blood composition into hypercoagulable state which leads to the formation of lower limb deep vein thrombosis, so the change of blood composition into hypercoagulable state should be the most important determinant of the formation. Therefore, those who have the above conditions should pay special attention to the prevention of thrombosis. Patients with surgery and trauma should move their lower limbs more often to promote faster blood flow in the lower limbs, in addition to cautious use of hemostatic drugs and use of anticoagulant drugs, when available. Long-distance travel should frequently leave the seat and walk around to avoid blood stagnation in the lower limbs.