The treatment of venous ulcers of the lower limbs has always been a difficult clinical problem, often difficult to heal, recurrent attacks, seriously affecting the quality of life of patients, routine drug changes and compression bandages and other therapeutic efficacy is not good. From January 2013 to April 2014, our department used VSD combined with blade-thickness skin slice implantation to treat 40 patients with venous ulcers of the lower limbs, and the therapeutic effect was exact, which is reported as follows.1. Data and methods General data: 40 cases in this group, 28 men and 12 women, aged 31-66 years old, with a course of disease of 6 months to 4 years. There were 14 cases of simple varicose veins combined with ulcers, 12 cases of cockett’s syndrome combined with ulcers, 8 cases of Buga’s syndrome combined with ulcers, and 6 cases of lower extremity deep vein post-thrombotic syndrome combined with ulcers. Wound area: 3cm*4cm~15cm*20cm.1.2.1 Preoperative treatment: all patients were given routine dressing change and symptomatic treatment to make the wound cleaner, the wound was taken for secretion culture, and sensitive antibiotic treatment should be given to those who had indications, and biopsy should be taken for longer ulcers and larger wounds to exclude malignant changes. Simple varicose veins combined with ulcers should be operated at the same time, Buga syndrome, cockett syndrome, lower extremity deep vein thrombosis syndrome should be intervened in advance to open the stenosis and occluded segment of the venous vessels, and then operated after 3-7 days.1.22 Surgical methods: (1) Cleansing: repeated flushing of wounds with saline, hydrogen peroxide, iodine, and thorough removal of necrotic tissues from wounds, and inactivation of wound margins and sclerotic tissues. (2) Surgery: patients with superficial varicose veins underwent high saphenous vein varicose vein ligation with extraction and stripping, smaller ulcers were taken from autologous skin flaps to directly cover the trauma, and larger ulcers were treated with blade-thick skin grafting for skin repair. The skin was taken with a roller blade in the anterior or lateral thigh according to the size and shape of the wound to take the appropriate size of the skin slice, all the grafted skin slice was poked with a sharp blade to make small, uniform and dense incisions, which on the one hand can expand the area of the skin slice, and on the other hand, to promote the drainage and avoid the accumulation of fluid under the skin slice. (3) Installation of VSD device: choose the appropriate size of VSD auxiliary material to cover the wound, and if the wound is large, use multiple pieces of auxiliary material to splice it together, so as to fully contact the wound without residual dead space, and if necessary, suture it with the edge of the wound; close the drainage tube and the VSD dressing with the film with bio-permeable properties; connect the drainage tube with the “Y” shaped connector, and connect it with the negative pressure suction to test the effect of negative pressure and confirm the leakage of the VSD. 1.23 Postoperative treatment: After surgery, the “Y”-shaped connector is connected to the central negative pressure suction device, the negative pressure is maintained at mmhg, continuous suction, and the affected limbs should be elevated by 30°, pay attention to whether there is any leakage of air, blockage of tubes, bleeding, local skin color and other conditions, and make timely and correct treatment accordingly. The device was removed 5~7d after surgery, routine dressing change was given, and the decision of whether to perform surgery again was made according to the healing condition of the wound.2. Results 40 patients were discharged from the hospital with healing. The average use of VSD 6d, 32 cases of all survival; 6 cases of skin piece survival 92%, including 2 cases of cockett syndrome patients, 4 cases of Buga syndrome patients; 2 cases of survival 60%, for the lower extremity deep vein thrombosis after syndrome patients, after dressing change wound healing. Figure 23, Discussion of the treatment of venous ulcers of the lower limbs has been a clinical problem, venous reflux and reflux obstructive lesions caused by venous hypertension, skin microcirculation disorders is the main cause of venous ulcer formation, lifting the cause of the disease is the first condition. The methods of preventing and treating ulcer formation include: compression therapy (such as the application of medical compression stockings) [3], routine dressing changes, surgical debridement and drainage, etc., and skin grafting can be performed after the traumatic granulation is fresh, but the results are poor, and it is difficult to heal, the course of treatment is long, and the traumatic surface is easy to be infected, which significantly reduces the quality of life of the patients, and brings pain and burden of life to the patients and their families.VSD was invented in 1992 by Germany, Fleischmann et al. Fleischmann et al. invented in 1992, the technology of medical foam attached to the wound, and a semi-permeable film to seal the wound, negative pressure drainage [1], can ensure that the wound is clean, effectively avoiding cross-infection, improve the drainage of the wound blood circulation, promote wound healing, and at the same time can reduce the number of dressing changes, shorten the duration of the treatment [2].The advantages of the VSD is to reduce the infection of wounds and to promote wound healing, because the VSD is a combination of open and open wound, and it is easy to heal, which is the reason that the VSD is a good way of reducing wound infections and promoting wound healing. The reason is that VSD turns open wounds into closed wounds, effectively prevents the invasion of external bacteria, changes the living environment of the main bacteria, inhibits their growth and reproduction, reduces the absorption of toxins, and accelerates the growth of granulation tissue. At the same time, negative pressure drainage out of the wound exudate, necrotic tissue, etc., reducing the wound toxins, various inflammatory mediators on the wound, the study has confirmed that the negative pressure environment on the wound surface can effectively promote wound healing, and its detailed mechanism will not be recounted here [4].The negative pressure attraction of the VSD makes the wound keep a low-oxygen or even hypoxic acidic environment, which greatly reduces the oxygen tension on the surface of the wound can effectively stimulate the repair signals. VSD promotes the release of fibrinolytic protein activator and other related enzymes to accelerate fibrinolysis, and the dissolution of old fibrous tissue can make the wound surface cleaner.VSD can also increase the blood perfusion of the wound surface, improve the microcirculation of the wound surface, and promote the proliferation and migration of the cells[5], which is a targeted treatment for microcirculation disorders in venous ulcers. In conclusion, VSD can reduce tissue edema, improve local microcirculation, accelerate the growth of fresh granulation tissue and promote wound healing. Meanwhile, for wounds requiring skin grafting, VSD can enhance the effect of skin grafting and shorten the course of treatment [6].Attention should be paid to the use of VSD: 1) Early and thorough debridement should be performed, especially foreign bodies, because these substances can be used as a good culture medium for bacteria and bacteria and toxins are an important cause of impeding wound healing; 2) Ensure that the wound is airtight and the tubular lumen is smooth, there can be no leakage, and negative pressure pressure should be up to the requirements, not too low or too high; 3) Ensure the wound seal and the tubular lumen is smooth, not leakage, and negative pressure should meet the requirements. Can not be too low or too high; 3) Observe the drainage tube continues to drain fresh bloody fluid, active bleeding occurs, bleeding should be stopped in time; 4) Observe the blood supply of the affected limbs, monitor vital signs, wound pain can be given to patients with analgesic treatment, if necessary, reduce the negative pressure. For patients with venous ulcers of the lower limbs, cancerous ulcer wounds and active bleeding wounds are contraindications to VSD. Combined with clinical experience, VSD is especially suitable for wounds with larger trauma, more exudation and infected wounds, while the difference in efficacy between small wounds with less exudation and conventional dressing changes has no obvious advantage.