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There are two types of venous thrombosis: one is thrombophlebitis, which means that inflammation is the first and thrombosis is secondary; the other is venous thrombosis, which means that thrombosis is the first phenomenon, the inflammatory process of the vein wall is Secondary, deep vein thrombosis of the lower limbs is the most common. The elderly not only have a high incidence, but also are prone to fatal pulmonary embolism, which deserves attention.

Basic Information

English name: Venous Thrombosis
Visiting department: Cardiology
Multiple groups: Seniors

Common causes: Slow blood flow, hypercoagulability, and changes in the lining of the vein
Common symptoms: Superficial vein thrombosis pain, redness, fever, swelling; inflammation of deep vein thrombosis is mild; asthma vein vein thrombosis is mostly asymptomatic; iliac vein femoral vein thrombosis is tender, etc.

Overview of Venous Thrombosis

There are two types of venous thrombosis: one is thrombophlebitis, which refers to inflammation as the first onset and thrombosis to secondary. The other is venous thrombosis, which refers to the phenomenon of thrombosis as the first phenomenon. The inflammatory process of the vein wall is secondary. However, deep vein thrombosis of the lower limbs is the most common. The elderly not only have a high incidence, but also are prone to fatal pulmonary embolism, which deserves attention.

Causes of venous thrombosis

Slow blood flow, hypercoagulability, and venous intimal changes are three important factors for venous thrombosis.

Slow blood flow

First of all, the elderly have poor physical strength, less activity, and more opportunities to stay in bed, which weakens the muscle elasticity of venous return. In addition, the elderly have more heart disease, poor heart function, and significantly reduced stroke volume. Causes systemic congestion; In addition, the incidence of abdominal tumors in the elderly increases. Both abdominal organs and tumors can compress the veins when supine. At the same time, the veins of the lower limbs are compressively blocked by tendons, ligaments and nerves in some places. Blood return, the elderly are susceptible to varicose veins, tortuous dilation of the veins, decreased elasticity, and most of them are accompanied by venous blood flow stasis in the lower limbs due to damage to the venous valves and communication branches.

2. Hypercoagulation mechanism

It is manifested by increased blood coagulability, increased fibrinogen activity, decreased fibrinolytic activity, and increased platelet aggregation. These aging changes are conducive to thrombosis. In some pathological conditions, such as fractures, trauma, surgical tissue damage, causing a large amount of thromboplastin to enter the blood circulation; dehydration of erythrocytosis, abnormal plasma protein and large vein intubation, infusion of hypertonic nutrient solution can cause blood concentration; pancreas Malignant tumors of the lung, ovary, and leukemia themselves can promote platelet destruction and release clotting factors to promote thrombosis.

3. Intravenous changes

Vein aging is characterized by rough intima and atrophy of the venous valve, and platelet adhesion easily occurs in the sinuses below the valve, forming a thrombus. Venous pacing catheters and electrodes can also cause venous intimal injury.

Clinical manifestations of venous thrombosis

Superficial venous thrombosis

Most are thrombophlebitis, which are more common in the limbs, and often involve the large saphenous vein, small saphenous vein, cephalic vein, guiyang vein and its branches. Symptoms are local pain, redness, fever, swelling, and elevated body temperature. Cord-thin thrombus can be felt in thinner parts of the subcutaneous tissue. Because the inflammation at the thrombus site is significant, it often adheres to the wall of the tube and rarely causes pulmonary embolism. If phlebitis develops further, deep veins can affect pulmonary embolism due to emboli detachment.

Deep vein thrombosis

In the beginning of the onset of thrombosis, veins are formed, followed by secondary inflammation at the thrombus site, so the inflammation is mild.

3. Calf vein thrombosis

Most patients are asymptomatic, and a few feel swollen and urgent calves. Symptoms worsened in standing, sitting, and walking. Some leg and foot edema, and gastrocnemius tenderness. Post-thrombotic syndrome can occur when the venous communication branch is invaded. If the disease is suspected, venography can be used to confirm the diagnosis.

4. Iliac vein femoral vein thrombosis

Symptoms are obvious. There is tenderness in the crotch and femoral triangle of the pit litter. There is stretching pain on the back of the thigh and gastrocnemius muscle when flexing the back of the foot. The inflammation of the acute attack is very serious. sense. Arterial spasm can occur when the inflammation is obvious, the skin is pale, the subcutaneous veins are dilated, the tenderness of the affected limb is obvious, and the arterial pulse can not be touched, which is called painful femoral swelling. If the lesion is large and invades the iliac vein and its branches of the pelvic vein, the lower extremity is highly edema and cyanosis, which is called painful femoral bruising. Severe cases can cause venous gangrene in the lower limbs and even shock.

5. Inferior vena cava thrombosis

It can be primary or develop from patellofemoral thrombophlebitis, which often occurs on the left and subsequently spreads to the inferior vena cava. Finally, it invaded the right iliac vein, so its signs were bilateral, and the rest were the same as the iliofemoral vein thrombosis.

6. Upper extremity thrombophlebitis

Rarely, it often extends from superficial veins to deep veins. It is common in thoracic tumors and aortic tumors to compress the subclavian vein or secondary to trauma. Its clinical manifestations are the same as that of lower extremity deep vein thrombophlebitis.

7. Postthrombotic syndrome

After a large vein in the lower extremity has formed a thrombus, it is difficult to dissolve and re-drain it naturally, resulting in thrombosis myogenesis and venous occlusion. Even if the venous valve is re-opened, insufficiency often occurs. Deep vein thrombosis often invades the vein branch. The condition caused dilation of lower limb capillaries and small veins, changes in the permeability of the tube wall, red blood cell escape, lymphatic circulation obstruction, subcutaneous tissue edema, hypertrophy, fibrosis, skin hemosiderin, leather-like changes, and eczema and ulcers. This condition is called postthrombosis syndrome, and its symptoms are edema, swelling, and even pain in the entire affected limb. Standing or sitting for a long time can make the symptoms worse.

Venous thrombosis

Laboratory inspection

Examination of the coagulation mechanism: It has been reported that the measurement of thromboglobulin present in the agglutinated platelets in the plasma can diagnose deep vein thrombosis. Measurements of platelet, coagulation factor, and fibrinolytic system activity can help determine the state of hypercoagulability, but cannot directly determine the presence of a thrombus.

2. Other auxiliary inspections

(1) or fibrinogen scan to check intravenous injection of or fibrinogen, the substance participates in coagulation, so it gathers at the venous thrombus. If the radiation dose measured from the body surface with a counter exceeds the original measurement value at that point, or more than 20% of the radiation dose at the corresponding site on the opposite side is positive.

(2) The former Doppler hemometry and impedance plethysmography are based on the characteristics that the frequency changes when the ultrasound meets a moving target (blood cells in the venous blood stream) and is proportional to the speed of movement; the latter is based on Under normal conditions, the characteristics of limb blood volume changing with changes in venous pressure during breathing; electrical impedance technology is used to determine the voltage changes caused by these small volume changes. When the main blood vessel is blocked, the limb volume does not change with breathing, so there is no voltage These two methods are simple, non-invasive, and can reflect the functional status of the veins, but the accuracy is poor. Small thrombus and occluded veins and thrombus in the collateral circulation-rich parts have not been detected yet.

(3) Infrared imaging is a non-invasive examination of deep vein thrombosis. This method is supplemented by plethysmography. Compared with venography, most deep vein thrombosis can be found. The coincidence rate of infrared imaging and venography is comparable. high.

(4) venography through the dorsal cutaneous vein or the calcaneus cavity into the contrast agent and then photograph the lower extremity, this method can detect the majority of calf vein thrombosis, can determine the location and scope of the thrombus, dynamic venography Venous valve function can be speculated.

Diagnosis of venous thrombosis

Superficial venous thrombophlebitis is often diagnosed by tenderness, swelling, and palpable cord veins at the site of the thrombus. The symptoms and signs of acute venous thrombosis and deep venous thrombosis of the femur are prominent, and it is not difficult to make a diagnosis. Diagnosis of venous thrombosis in other parts, especially insidious onset and lack of symptoms, is difficult, and venous thrombosis is often suspected only after secondary pulmonary embolism. The patient's local skin temperature increased, tenderness along the veins of the inner thigh, the sphygmomanometer cuff was tied to the thigh, and pain in the affected limb appeared when the pressure was 60 to 150 mmHg, which helped the diagnosis.

Venous thrombosis treatment

The venous thrombosis of the elderly is mainly conservative treatment in principle, and surgical treatment can be performed according to the situation if necessary. Superficial venous thrombophlebitis can be treated with non-hormonal anti-inflammatory agents, sedatives, heat compresses, ultrasound, and ultraviolet rays without restricting activities and anticoagulation therapy. Deep venous thrombosis, especially acute iliac, femoral and calf deep venous thrombosis, is prone to concurrent pulmonary embolism, and the risk is greatest within two days after the onset of disease. Therefore, once diagnosed, you should stay in bed for more than 72 hours to perform anticoagulation and dissolution. Suppository treatment. Anticoagulation and thrombolytic therapy are used in patients without contraindications, and the elderly over 70 years old should be used with caution.