What Is the Common Iliac Vein?

The venous blood flow of the lower extremity is slow due to various reasons, and the blood is in a hypercoagulable state, which accumulates in the lower extremity vein and forms a thrombus. If the acute lower extremity venous thrombosis is not diagnosed and treated in time, some patients may cause pulmonary embolism due to the shedding of the thrombus. Lower extremity venous thrombosis can occur in any part of the lower extremity. There are two types of clinical common: calf muscle venous plexus thrombosis and patella venous thrombosis.

Basic Information

English name

thrombosis of deep vein of lower extremities

Visiting department

Vascular surgery

Common causes

Prolonged illness in bed, trauma or fracture, major surgery, trauma, after surgery, large area burns, pregnancy, etc.

Common symptoms

Pain and tenderness in the affected limb, swelling, purple skin, etc.

Causes of lower extremity venous thrombosis

Stasis of blood flow

Blood stasis is the primary cause of deep vein thrombosis of the lower limbs. Bedriding due to chronic illness, trauma or fracture, major surgery, pregnancy, childbirth, sedentary long-distance travel by car or plane, or prolonged meditation and squatting can make blood flow slow, stagnant, and cause lower extremity venous thrombosis form. The left iliac vein is susceptible to compression of the right iliac artery (Cockett's syndrome), causing distal venous reflux disorders and causing thrombosis.

2. Hypercoagulable state of blood

Such as trauma, post-surgery, large-scale burns, pregnancy, postpartum, etc. can increase platelets, increase adhesion, and easily form blood clots. The other type of AT-III, PC, PS, and t-PA that are reduced or have abnormal activity due to congenital autosomal dominant inheritance is called "hereditary thrombosis syndrome", which can also lead to venous thrombosis.

3. Vein wall injury

The vein wall is affected by any factor. When mechanical damage, infectious and chemical damage are common, the collagen in the basement membrane and connective tissue of the lining of the vein is exposed. Platelets subsequently adhere to it, aggregate, and release many Biologically active substances, such as catecholamines, serotonin, etc. At the same time, under the action of platelet thrombin, arachidonic acid forms prostaglandins PGG2, PGH2 and other substances. These substances can aggravate the aggregation of platelets and help to form thrombus.

Clinical manifestations of lower extremity venous thrombosis

1. Primary iliac-femoral vein thrombosis

Thrombosis is located in the iliac-femoral vein, and its incidence is lower than that of the calf plexus vein thrombosis, which is more common on the left side.

The iliac-femoral vein is the main channel for venous blood flow in the entire lower extremity. Once thrombosis occurs, it rapidly develops. The main clinical manifestations of this disease are: pain and tenderness in the affected limb, inflammatory reactions triggered by thrombosis can cause local persistent pain; dysfunction of distal venous blood reflux causes swelling, and symptoms worsen when standing, on the iliac-femoral vein path Cords and tenderness can often be touched; Swelling, caused by severe venous reflux disorders, is generally quite severe; The skin color of the affected limb is purple, and severe cases can cause variegated or even gangrene; Acute limb pulsation in severe cases Weakened and disappeared; Superficial varicose veins are compensatory, and the acute phase is not obvious.

The outcome of primary iliac-femoral vein thrombosis is: fibrinolysis and recanalization; limitations and mechanization; thrombus expansion: retrograde expansion can affect the entire deep vein system of the lower extremity; antegrade expansion may invade the inferior vena cava, such as Thrombosis can lead to fatal pulmonary embolism.

2. Secondary iliac-femoral vein thrombosis

Thrombosis originates from the venous plexus of the calf muscle and can affect the entire iliac-femoral venous system during anterograde expansion. This is a mixed type and is the most common type in clinical practice. Its characteristics are: the onset mode is mostly concealed; the symptoms are mild at the beginning, and many patients are not found until the symptom of the iliac-femoral vein is involved, so the actual disease period is longer than the symptom period; nutritional changes in the boot area , Including desquamation, hyperpigmentation, eczema-like changes, and ulcers, because the deep and shallow communication veins of the lower leg often have lesions, so the evolution is much faster and more severe than the primary type.

3. Femoral bruising

In 1938 Gregoire described severe diffuse iliac-femoral vein thrombosis involving venous limbs, called femoral bruising, which is not clinically rare. This is the most severe type of deep vein thrombosis in the lower limbs. The entire venous system of the lower limbs includes Potential collaterals are almost all blocked, venous pressure rises sharply, limbs are severely painful with obvious swelling of the entire affected limb, the skin is shiny and cyanotic, and the skin temperature is reduced. The affected limb is severely affected by arterial spasm and / or gap syndrome Swelling, ischemia, or even necrosis. This is venous or wet gangrene. Shock can be caused by a large amount of body fluid entering the affected limb and sudden limb pain in a short period of time.

Lower extremity venous thrombosis

1. Doppler flow and plethysmograph examination

It is a non-invasive examination method that helps to determine the blood return and blood supply of the affected limb.

2. Radionuclide venography

Injection of nuclide-labeled ^[125] I-labeled human fibrinogen from the dorsal vein of both feet can be absorbed by fresh thrombus, so after blocking the thyroid iodine function, intravenous injection of this agent is used to scan both lower limbs, if radiation is observed Sudden increase or accumulation of agents can help diagnosis.

4. Venography

The vein can be directly visualized, and the presence or absence of blood clots can be judged. Its scope, shape, and collateral circulation conditions not only help determine the diagnosis, but also directly observe the treatment results. Although this method is the most reliable, when the condition is too severe, it is not necessary to force the completion of this examination, and the angiography itself may aggravate the lesion.

5. Determination of venous pressure

It is helpful to understand the condition and observe the development. It can be measured alone or during imaging.

Diagnosis of lower extremity venous thrombosis

1. More common in postpartum pelvic surgery, orthopedic surgery, trauma, advanced cancer coma or long-term bedridden patients.

2. Severe onset, swelling of the affected limb, stiff pain, exacerbation after activity, often accompanied by fast fever pulses.

3. Tenderness at the thrombus site. The distal limb of the thrombus along the blood vessel can be swollen, or the whole limb is swollen, the skin is blue-purple, the skin temperature is reduced, the posterior tibial artery pulse is weakened or disappeared, or venous gangrene appears; When it extends to the inferior vena cava, there is obvious edema in both lower limbs, hips, lower abdomen and external genitalia. Thrombosis occurs when the venous plexus of the calf muscle is positive for Homans sign and Neuhof sign.

4. The late thrombus absorption is mechanized, often leaving veins, insufficiency, superficial varicose veins pigmentation, ulcer swelling, etc., known as deep vein thrombosis syndrome. It can be divided into: the peripheral type is mainly blood reflux; the central type is mainly blood reflux disorder; the mixed type has both blood reflux and reflux disorder.

5. Thrombosis can cause pulmonary embolism.

6. Radiofibrinogen test Doppler ultrasound and venous blood flow examination can help diagnose venography and confirm the diagnosis.

Lower extremity venous thrombosis treatment

Surgical treatment

Surgical thrombectomy is an effective method to eliminate thrombus, which can quickly relieve venous obstruction and relieve swelling symptoms.

2. Inferior vena cava filter implantation to prevent pulmonary embolism

Implantation of the inferior vena cava filter is an important method to prevent fatal pulmonary embolism caused by thrombotic shedding in the acute stage. It is a minimally invasive operation by placement by interventional method. Absolute indications include: contraindications to anticoagulation, new pulmonary embolism during anticoagulation, or those who intend to undergo pulmonary artery embolization. Relative indications include: patients who have had pulmonary embolism, patients who are planning to undergo other surgical procedures, or other patients who are expected to have a higher risk of shedding. The filter can be a permanent type or a removable type, and the new type of removable filter can be left in the body permanently or removed according to clinical needs.

3. Drug treatment

Intravenous application of heparin, although it can immediately act as an anticoagulant, thereby exerting a thrombolytic effect by mobilizing endogenous cytosinogen, but seems to be more passive than direct thrombolytic agents. Because streptokinase is antigenic and often causes a pyrogenic reaction after intravenous administration, urokinase is advocated.