Lower extremity deep vein thrombosis is a common and frequent disease, and the treatment effect is not ideal, often leaving lower extremity deep vein obstruction or venous valve insufficiency, and pulmonary embolism can occur in some patients. Therefore, how to improve the therapeutic effect and reduce the occurrence of sequelae and complications has become the focus and difficulty of clinical treatment.
Treatment of lower limb deep vein thrombosis
1.Non-surgical treatment: It is applicable to peripheral type and central type and mixed type which are more than 3 days old. The therapeutic effect varies from report to report. However, one thing is certain, that is, for mixed type thrombosis, even if the symptoms are relieved, the vast majority of deep veins cannot be completely recanalized in a short time.
(1) Bed rest and elevation of the affected limb: Bed rest for 1 to 2 weeks, avoiding activities and straining to defecate to avoid dislodging the thrombus. Elevate the foot of the bed by 20-25cm, so that the lower limb is higher than the heart level, which can improve the venous reflux and reduce edema and pain. When getting out of bed, elastic stockings or elastic bandages should be worn.
(2) Thrombolytic therapy: commonly used drugs include urokinase, streptokinase and rt-PA, etc.
(1) Urokinase: There is no unified medication standard, ranging from 100,000~200,000 IU/day to 500,000~1,000,000 IU/day, with continuous application for 10~14 days. Urokinase has a certain fibrin-lowering effect and needs to be monitored for fibrinogen, APTT and PT, etc. When fibrinogen is lower than 1.5g/L, monitoring should be strengthened or even discontinued.
②Streptokinase: It is extracted from the culture of Streptococcus haemolyticus and has antigenic properties. It should not be used if streptokinase has been applied within 6 months or if streptococcal infection has occurred.
④rt-PA recombinant tissue-type fibrinogen activator, which can selectively activate fibrinogen and promote fibrin degradation. The first dose of 500,000 IU is administered intravenously over 30 minutes, followed by 50,000 IU every 8-12 hours for 7 days.
(3) Anticoagulation therapy: often used as a follow-up to thrombolytic therapy and surgical thrombectomy, commonly used anticoagulants are heparin and coumarin derivatives.
Heparin: very effective anticoagulant drug, the general adult dose of 1 ~ 1.5mg/Kg, every 4-6 hours intravenous or intramuscular injection once, and monitor the test tube method clotting time, to control in 20-25 minutes is appropriate, if less than 15 or more than 30 minutes, the dose should be increased or reduced. If an overdose causes bleeding, fisetin antagonism can be applied.
②Low-molecular heparin: precise efficacy, no need to monitor. The commonly used dose is 4000~5000 IU, injected subcutaneously every 12 hours.
③Coumarin derivatives: commonly used are warfarin, new anticoagulation and new bicoumarin, etc. Generally, the effect begins to occur 24 to 48 hours after the drug is administered, so it is often applied 2 to 3 days before stopping heparin or low-molecular heparin. The duration of medication is maintained for 3 to 6 months.
In addition, low molecular dextran, aspirin and pansentine can also be added to dispel aggregation treatment; Chinese herbal medicine treatment, can be used to dispel thrombosis and pass through the veins soup (Danshen, Chuanxiong, Angelica, Sanshou, Niu Xi, leech, Tu Bei worm, piercing beetle) plus flavor.
2.Surgical treatment: venous thrombosis removal Applicable to central type and mixed type within 3 days. It is easy to use Fogarty catheter to remove the thrombus, but it is necessary to prevent the thrombus from dislodging and pulmonary embolism during the operation, and pay attention to anticoagulation after the operation to prevent the recurrence of thrombus. Some patients can not pass the catheter due to compression and occlusion of iliac vein.
3.Tubing thrombolysis: placing the catheter in the thrombus, which is conducive to the action of drugs, is more effective for thrombus within 3 days, and the duration of tubing placement is usually about 10 days.
Post-deep vein thrombosis syndrome i.e. post-thrombotic sequelae, the incidence of which is more than half, manifests as varicose veins, skin pigmentation, ulcers, etc., which seriously affects the quality of life of patients. According to the different types of original lesions, the post-thrombotic syndrome of lower limb deep vein is also divided into three categories.
1, peripheral type: the thrombosis of the breeding reproduction range, terminating in the distal side of the N vein, the late passage rate of 95%, the main lesion for the destruction of the valve and ankle traffic branch insufficiency, the foot boot area quickly appear dystrophic changes. Treatment should be less standing, elevating the affected limb, applying compression with elastic stocking force or elastic bandage support, and parallel traffic branch ligation.
2.Central type: The remaining thrombus is confined to the iliofemoral vein segment, which is not recanalized, mainly manifesting as distal venous reflux obstruction, and the function of the main venous valve and ankle traffic branch is not damaged. Saphenous vein graft diversion is appropriate for treatment.
3.Mixed type: the most common, clinical manifestations have both the above two types of characteristics, both venous reflux disorder and deep vein and traffic branch valve insufficiency, the treatment is more difficult. If reflux obstruction is the main type, various kinds of diversions are feasible; if reflux is the main type, transplantation of venous segment with valve, superficial femoral (distal)-deep femoral vein or saphenous vein (proximal) transposition diversion and semitendinosus-biceps N vein valve replacement are feasible.
Prevention and treatment of pulmonary embolism: Most emboli are very small in size, and even when they fall off into the pulmonary artery, there is no clinical manifestation, so they are easily ignored. However, if there is no prevention and treatment, they will repeatedly fall off and embolize into the pulmonary artery for a long time, and after the thrombus is mechanized, chronic pulmonary embolism will be formed, causing embolic pulmonary hypertension and pulmonary heart disease, which is difficult to treat and has a poor prognosis. In clinical practice, what often draws our attention is some lower extremity deep vein thrombosis with obvious clinical manifestations, because its embolus is large, if several emboli are dislodged and embolized in more than one segment of the pulmonary artery in a row, it can cause fatal clinical events, at least in a short period of time, which can cause deterioration of cardiopulmonary function. However, in practice, the incidence of the former is much higher than that of the latter. It should be noted that many patients die from their primary disease, but chronic pulmonary embolism is often an important cause of the difficulty in correcting the primary disease.
In the past, the prevention of pulmonary embolism was mainly based on inferior vena cava folding or ligation, which often resulted in impaired venous return to the lower extremities. In recent years, inferior vena cava filter placement has been widely accepted and used. The inferior vena cava filter can be placed in those who are likely to have pulmonary embolism; anticoagulation and thrombolysis are contraindicated. Especially for patients with DVT who have already had pulmonary embolism, inferior vena cava filter placement can be very effective.