Why is it necessary to create an arteriovenous fistula? During hemodialysis, human blood needs to enter the dialyzer quickly and flow back into the body after washing. The superficial veins are easy to puncture, but the venous blood flow is too slow to meet the requirements of dialysis; the arterial blood flow is high enough to meet the requirements of hemodialysis, but the site is deeper, more difficult to puncture and not easy to use repeatedly. Therefore, surgery is needed to connect the artery to the superficial vein, called arteriovenous endovascular surgery, so that the superficial vein is flowing with arterial blood, so that the blood flow can meet the requirements of dialysis. It is the “lifeline” of the uremic patient and needs to be protected. What are the most common types of arteriovenous fistula procedures? There are two types of arteriovenous fistulas: autologous and grafted arteriovenous fistulas. Autologous arteriovenous fistula is a direct anastomosis between a superficial vein and an artery, and during hemodialysis, a superficial vein is punctured. When the patient does not have a suitable superficial vein to puncture or when the patient is too obese and the superficial vein is too deep to be punctured, endovascular grafting is performed. A section of the graft is buried under the skin, and the two ends are connected to the own artery and vein. The most common material used is PTFE artificial blood vessel. What is the post-operative care? Wash with soap daily to prevent infection; elevate the operated limb to promote venous blood return to reduce swelling; change the puncture site at each hemodialysis; wear loose underwear with cuffs on the operated limb and do not wear too tight accessories; do not compress the operated limb when sleeping; avoid hypotension. Avoid taking blood pressure and drawing blood from the operated limb; do not lift too heavy objects; do some fistula exercises to promote fistula maturation; learn how to determine if the fistula is patent by touching the vein on the operated side with the hand on the non-operated side; if you feel tremors or hear a vascular murmur, it is patent. Check the fistula daily to make sure it is open. How do I do fistula exercises? If you squeeze and hold a rubber exercise ball with the operated side hand 3-4 times a day for 10 minutes each time, you can also use your hand, a tourniquet or a blood pressure gauge cuff over the anastomosis and gently apply pressure until the vein is moderately dilated and release it every 15-20 minutes, which can be repeated 3 times a day. Hot compresses or forearm immersion in hot water 2-3 times a day for 15-20 minutes each time. The above methods can be used individually or in combination. What is the appropriate blood pressure to maintain? A systolic blood pressure of 130-150 mmHg and a diastolic blood pressure of 80-90 mmHg are generally required; too low a blood pressure can lead to blockage of the fistula. How long after surgery can I use the fistula? Autologous arteriovenous endovascular fistulas need to wait until the fistula is “mature”, i.e., the veins are dilated and the walls are hypertrophied, before they can be punctured for hemodialysis, usually 4-8 weeks after surgery. Theoretically, there is no need to wait for the vessels to “mature” after surgery, and they are ready to be punctured immediately. However, the local swelling after surgery often makes it impossible to feel the artificial vessels, and since the artificial vessels have not yet healed with the surrounding tissues, hematoma and infection can easily occur after puncture, which affects the use of the fistula. What issues should be noted in hemodialysis? Choose the correct puncture point, avoid anastomotic puncture, and the venous puncture point should be as far away from the arterial puncture point as possible to reduce blood recirculation. Never puncture at a fixed point, so that the whole arterialized vein is used equally and the thickness of the vessel is uniform, avoiding fixed puncture or small puncture and causing damage to the lumen of the vessel that uses more. Adopt the correct hemostasis method, mainly using compression hemostasis method, the arm can be slightly elevated to reduce the venous reflux resistance and accelerate hemostasis. Pressure hemostasis is appropriate, in order not to ooze blood and to be able to palpate tremor and hear vascular murmur. Do good personal hygiene. What are the possible postoperative complications? Common postoperative complications include infection, thrombosis, endothelial proliferation, pseudoaneurysm, distal limb ischemia, and heart failure. Complication rates are generally higher for graft-vessel arteriovenous fistulas than for autologous arteriovenous fistulas. What are the conditions that require immediate medical attention? Tremor or loss of murmur suggests fistula blockage; localized redness, swelling, or chills or hyperthermia, and fluid leakage from the wound suggests infection. What is the significance of vascular ultrasonography? Pre-operative use can help select appropriate arteries and veins, detect narrowing, occlusion and other lesions, and improve the success rate of surgery. Postoperative use can monitor the stenosis of the fistula, and if the stenosis is >50%, early intervention by balloon dilation or placement of an endovascular stent can be used to reduce the occurrence of thrombosis and improve the life of the fistula.