Overview Hemodialysis refers to the channeling of blood from a patient with renal failure out of the body, exchanging it through a dialysis machine and then back into the body; this channel is known as vascular access. Hemodialysis and peritoneal dialysis are the two main alternative treatments that patients with renal failure rely on for survival. The completion of hemodialysis depends on good vascular access. 1960 Quinton et al. connected the patient’s limb arterial and venous blood vessels with polytetrafluoroethylene tubing (PTFE) outside the body, the first time to establish arterial fistula. 1966 Brescia and Cimino invented autologous arterial fistula, so that hemodialysis technology has entered a new era, and it is still the most safe and effective vascular access for patients with chronic renal failure. In the 1970s, transplantation of vascular endovascular fistulae was introduced on a trial basis. Vascular access is mainly the following three ways: hemodialysis temporary vascular access refers to the vascular access can be established in a short period of time and can be used, including arteriovenous fistula, direct arteriovenous puncture, percutaneous central venous catheter puncture placement of temporary hemodialysis tubing, etc.; semi-permanent hemodialysis access refers to the long-term cannula (Permcath), which maintains a longer period of time, and is generally advocated to be used for 6 months to 2 years. Common complications of temporary and semi-permanent cannulae include thrombosis, pneumothorax, hemothorax, bleeding, superior vena cava stenosis, low dialysis flow, infection, sepsis, etc.; long-term hemodialysis vascular access refers to the vascular access that can be used for a long period of time in hemodialysis, which is mainly various kinds of arteriovenous fistulae, and it is suitable for maintenance hemodialysis patients. This article focuses on the establishment of permanent vascular access and the management of complications and other complex situations. Establishment of arteriovenous access for hemodialysis To create an arteriovenous fistula for hemodialysis, surgery has irreplaceable advantages: directness, convenience, and variety of surgical options. Surgical creation of an autologous endovascular fistula for dialysis, commonly used cephalic vein and radial artery anastomotic fistula (Brescia-Cimino AVF). The ulnar artery and vital vein, the brachial artery and median elbow vein, and the lower extremity arteries and saphenous vein are also options for intra-articular fistulas. The common sites for intra-autogenous fistulas are generally the upper extremity followed by the lower extremity and the radial followed by the ulnar. The common site of intra-auto fistula is preferred to the non-dominant side of the limb, then the dominant side of the limb, and finally the special site. Snuff bottle arteriovenous fistula can maximize the use of blood vessels, the disadvantage is that it does not conform to the principle of aesthetics, and the period of use is shorter. The elbow arteriovenous fistula is prone to aneurysm at the puncture site, and care should be taken to ensure that the fistula is less than 5 mm, or to restrain the anastomosis to prevent excessive return blood flow. Venous transposition is another way to establish the autologous fistula, the author experience this way although increase the skin incision, but can facilitate the patient dialysis for a long time. Artificial vascular arteriovenous fistula is mainly suitable for patients with poor vascular conditions and patients who cannot reuse their own blood vessels after multiple endovascular operations. In chronic renal failure (CRF) patients, due to long-term infusion therapy, superficial veins are often occluded, can also choose to use autologous vein grafts, e-PTFE artificial blood vessels to create endovascular fistula, the specific surgical methods are various. Artificial vascular arteriovenous fistula commonly used forearm brachial artery DD elbow vein collateralized artificial vascular fistula, forearm flexor artery DD elbow vein straight artificial vascular fistula, lower extremity femoral arteriovenous collateralized artificial vascular fistula, lower extremity femoral artery DDN vein artificial vascular fistula, subclavian artery DD subclavian vein artificial vascular fistula. Lower extremity artificial vascular fistulas are only used when graft vascular access cannot be established in the upper extremity. Because patients with uremia are often combined with vascular occlusive disease or diabetes mellitus, which may be combined with distal limb ischemia, the graft vascular anastomosis is close to the groin, and the incidence of infection is higher. Special such as superficial femoral artery root and abdominal wall superficial vein collateral bypass, graft vessels through the subcutaneous tunnel in the axillary artery, femoral artery and vein between the straight bypass, the clinical use of less. Establishment and use of arteriovenous endovascular fistula, as long as possible maintenance dialysis time. During the operation, pay attention to the gentle operation, the vein end as far as possible to eliminate fatty tissue; pay attention to the effect of venous valves; graft blood vessels through the tunnel should avoid twisting, angulation and pressure; graft blood vessels across the joints to avoid the impact of vascular compression and joint activity; when the superficial veins can not be used, whether to use the deep brachial vein is still controversial; microscopic anastomosis is conducive to long-term patency rate; suture skin should not be too tight, wound dressings do not The wound dressing should not be too tight so as not to compress the vascular bridge; do not use the endovascular fistula too soon after the operation; adopt the stepped puncture method when puncturing; adopt the fixed-point compression after dialysis and so on. Complications of hemodialysis access and surgical management of complex situations Surgical re-treatment of hemodialysis access is a more difficult situation. Common complications of vascular access include thrombosis, insufficient blood flow (anastomotic stenosis, collateral shunt, venous inability to mature), congestive heart failure, infection, blood-stealing syndrome, swelling syndrome, pseudoaneurysm, varicocele syndrome, and so on. 1, pseudoaneurysm Hemodialysis endovascular fistula pseudoaneurysm often requires surgical intervention due to its gradual increase in size. Surgical treatment is the most important method of pseudoaneurysm, can be used to repair, excision of pseudoaneurysm to rebuild a new fistula, ligation and other surgical procedures, but need to pay attention to intraoperative thrombus dislodgement leading to the risk of pulmonary embolism. Most pseudoaneurysms have attached wall thrombus formation, and intraoperative caution, gentle thrombus removal, and blood reversal can reduce the incidence of pulmonary embolism. The author has reported 20 cases of pseudoaneurysms of hemodialysis endovascular fistulae, 16 cases of pseudoaneurysms of the upper limbs, and 4 cases of pseudoaneurysms of the lower limbs formed by artificial vascular collaterals, all of which were treated by surgical repair or replacement. In 2 of these cases, the artificial blood vessels were concentrically and uniformly dilated, resembling true aneurysms, and no rupture orifices were seen. No such cases were named in the literature, and it is worth discussing whether they should be called true aneurysms or pseudoaneurysms. Early puncture leading to a pseudoaneurysm is often successful with ultrasound-guided compression, requiring short-term cessation of anticoagulation and heparin-free dialysis without surgical intervention. Recently intervention has been used in the management of pseudoaneurysms.Najibi et al. reported 10 cases of pseudoaneurysms with arteriovenous fistulas isolated with a wallgraft. Immediate dialysis treatment can use the same period of temporary venous cannulation dialysis, if the repair of artificial vascular collaterals, the same period of temporary venous cannulation is not necessary, can be used directly with the unrepaired segment puncture hemodialysis. 2, postoperative heart failure The arteriovenous fistula is a group of low-resistance collateral circulatory system, arteriovenous fistula can cause high output heart failure in maintenance hemodialysis patients. Anemia, water electrolyte disorders, acid-base imbalance, myocardial trophic disorder, hypertension, and hemodynamic changes after arteriovenous fistula surgery is related to heart failure, arteriovenous fistula causes or aggravates the mechanism of heart failure is mainly related to the size of the anastomosis, blood flow and secondary blood volume increase. The pharmacological approach to heart failure has evolved into a combination of symptom control and prevention. Surgical management of arteriovenous fistulas with excessive reflux leading to heart failure begins with the reduction of excessive blood reflux into the heart, which can be accomplished by the following methods: external compression of the arteriovenous fistula, which directly reduces or blocks reflux into the heart, with the disadvantage that this is prone to lead to thrombosis of the hemodialysis access. Application of the band-ring technique to narrow the anastomosis or its proximal access to limit the amount of blood returned to the heart. If the varices or side branches are widely communicated, it is recommended to ligate the arteriovenous fistula from the anastomosis, then the symptoms of heart failure are often improved. 3, thrombosis Thrombosis is the main factor in the failure of endocardial fistula, early thrombosis occurs in the short postoperative period, the main reason is the anastomosis of the twisted, angular, bandage compression, as well as factors such as low blood pressure, dehydration or hypercoagulable state. Postoperative close observation of vascular murmur and tremor, timely detection of thrombosis, as far as possible to avoid thrombosis factors. Thrombolysis or incision to remove the thrombus is effective, the establishment of a new endovascular fistula is another option. 4, endocardial stenosis is mostly seen in the venous end of the anastomosis, mainly related to their own vascular conditions, anastomosis technology, endocardial fistula maintenance technology. Blood transfusion and a large number of erythropoietin application, artificial blood vessel arteriovenous fistula occlusion opportunity increases. The means to deal with the stenosis of the endocardial fistula are drug treatment, balloon dilatation and surgical three methods, balloon dilatation is generally suitable for short-segment stenosis. Clinically, central venous stenosis caused by venous cannulation is more common. After the implantation of semi-permanent hemodialysis tubing, due to venous stenosis compression, thrombosis, infection, tubing distortion and other reasons, resulting in the inability to dialyze or dialysis flow is insufficient. Thrombolysis, replacement of dialysis tubing (e.g., temporary dialysis tubing replaced with permanent hemodialysis tubing), and creation of autologous or artificial vascular fistulae can be taken to deal with the problem. 5, distal blood theft syndrome arteriovenous fistula distal limb ischemia is a serious complication of arteriovenous fistula surgery, the reason is that the arteriovenous fistula shunt arterial blood so that the arterial blood supply of the distal anastomosis declined, and at the same time, due to the endothelial hyperplasia of the anastomosis near the blood vessels, distal venous reflux is impeded, the pressure is increased and aggravate the symptoms of ischemia. Patients with renal failure combined with atherosclerosis and diabetes mellitus are more prone to blood-stealing syndrome. The distal vein of the lateral anastomosis is ligated, and the fistula is changed to a functional end-to-end anastomosis. Narrowing the arteriovenous fistula anastomosis can reduce the degree of blood theft. Other vascular access problems such as varicose veins, swelling syndrome, inadequate blood flow, failure of veins to mature, and infections need to be managed in a specialized manner with reference to the general principles of treatment.