Because hemodialysis needs to be carried out regularly for a long time, it is necessary to establish a vascular pathway with repeated puncture and sufficient blood flow for blood drawing.
Such access is the main vascular access of hemodialysis patients and the lifeline to maintain their survival. Clinically, the "short circuit" between arteries and veins is artificially caused by surgical methods, and the standard term is arteriovenous fistula.
Of course, external fistula was also used in the early days, that is, silicone tube was used to directly connect the artery and vein, but it is basically not used now because of its complicated operation, easy infection and great damage to blood vessels. There are also many blood vessels on the surface of human body. Generally speaking, blood collection and even blood donation are directly puncture the vein of the forearm. Why should hemodialysis establish arteriovenous fistula to draw blood? This is because hemodialysis needs a fast and stable blood drawing speed in order to ensure the effect and prevent coagulation, and it is easy to puncture and repair because of frequent dialysis.
The superficial vein is not filled enough, and the venous blood cannot flow out to the dialysis machine in large quantities, so the dialysis effect is not ideal. However, the location of the artery is too deep, the puncture is difficult, and the vascular repair is slow, which is not conducive to repeated puncture. Arteriovenous fistula surgery is to use surgery to establish such a blood channel for long-term hemodialysis.
The artery is anastomosed with the superficial vein, and the arterial blood with large flow and fast flow rate is directly introduced into the superficial vein, which ensures sufficient blood flow and reduces the difficulty of puncture. Of course, if the diameter of the patient's own vein is too small or too deep, or it is hardened and narrow, which is not suitable for direct arteriovenous anastomosis, the doctor will use the artificial blood vessel for hemodialysis to be placed under the skin as the connection between the artery and the vein. After a few weeks, the artificial blood vessel will heal with the surrounding tissues, and blood can be drawn from this artificial blood vessel during hemodialysis.
Dialysis vascular access is usually done in unaccustomed upper limbs: for right-handed people, it is placed on the left arm; If you use your left hand, put it on your right arm. Vascular access for dialysis is usually located in the wrist near the hand.
If the vein is very thin (female, elderly or diabetic), it can be placed near the arm center (high position). If the vascular access cannot be placed on the upper limb, an arteriovenous catheter can be used and placed on the thigh.
Because the arteriovenous fistula of hemodialysis must be 2? It takes 6 weeks to mature, so patients with renal failure should undergo arteriovenous fistula surgery as soon as possible when hemodialysis is possible to avoid the pain and danger of deep vein intubation when the internal fistula is immature. Once hemodialysis is started, arteriovenous fistula is almost equal to the life of a kidney friend, so we must take good care and check the blood vessels regularly.
As long as the vascular access of dialysis is unobstructed, under the condition of regular and effective hemodialysis, kidney friends can live a happy life.
2. Why do you want to do arteriovenous fistula?
1. Arteriovenous fistula is a common vascular access for maintenance hemodialysis patients.
2. Safe, with sufficient blood flow (200~300ml/min) and less chance of infection.
3. The use of general internal fistula can last for 4~5 years.
4. It does not affect the daily life of patients.
5. Easy to puncture, etc.
3. How to construct arteriovenous fistula?
At present, two surgical methods are mainly used for arteriovenous flaccidity plasty in clinic.
(1) The suture method can be end-to-side anastomosis, end-to-end anastomosis and side-to-side anastomosis according to the surgical site, arteriovenous distance and the ratio of mouth diameter. Intermittent suture is generally used for end-to-end anastomosis.
Side-to-side anastomosis generally adopts continuous suture or intermittent suture, but generally one side adopts continuous suture and the other side adopts intermittent suture. ① Take wrist internal fistula as an example: 6? Seven zero stitches, 8? 9 0 needles, with needles at both ends, which is convenient to enter the needle from the lumen and speed up the suture.
The skin incision should be staggered with the internal fistula blood vessels to be made as far as possible to prevent vascular stenosis caused by scar compression of the incision in the future. ② Anastomotic patency test: At the end of anastomosis, pulse and tremor can be felt at the venous end of anastomosis, and vascular murmur can be heard.
If there is only pulsation without tremor and blood murmur, it should be suspected that there is thrombosis near the heart. It is necessary to reopen the anastomosis, insert the No.3 Fogarty catheter in the proximal direction of the vein, remove the thrombus and re-anastomose.
In the operation of burning artery without ligation, the pulse of radial artery at the distal end of anastomosis should be felt. It should also be noted that blood vessels that have been in a free state for a long time are prone to imperceptible vascular distortion during vascular anastomosis, which affects the smooth blood flow and should be prevented and eliminated.
③ Treatment of vasospasm: After opening the vascular clamp, the blood flow is insufficient, which is often caused by vasospasm. Analgesia, sedation, warm saline wet compress and local infiltration of 1% procaine or lidocaine can be observed as appropriate.
When sewing subcutaneous and skin, the tension should not be too large. No pressure is applied when dressing, so as not to oppress the blood vessels.
After operation, anisodamine (654-2) 10mg can be injected intramuscularly, twice a day for 3 days. Systemic anticoagulation does more harm than good. Considering the bleeding tendency of uremia, it is rarely used now.
However, for patients with hypercoagulable state, anticoagulants and antiplatelet aggregation drugs can be used to repeatedly form thrombosis and eliminate mechanical causes. Antibiotics and delayed stitches can be used as appropriate.
(2) Titanium wheel nail method ① Specification of titanium wheel nail: diameter 2 is generally adopted. 0 mm, 2.
5 mm, 3 mm. 0mm 3 kinds.
② Operation method: routine disinfection, laying sterile towel, anesthesia, skin incision, separating and releasing the artery and vein to be anastomosed at the selected operation site by suture method, disconnecting the artery and vein respectively and ligating the distal end after blocking the artery, blocking the blood flow at the proximal end with a vascular clamp, fixing the nail with appropriate caliber on the anastomosis clamp with corresponding specifications, and passing the free ends of the artery and vein through the holes at the rear side respectively. Carefully lift the periphery of the blood vessel with a hook or pointed toothless pliers, and hang it symmetrically on the four wheel nails. Press the nail tip with a perforated needle sleeve to make the wheel nail penetrate into the intima from the adventitia of the blood vessel and fix it firmly. Heparin saline was perfused into the vein end, then the wheel nail with broken blood vessel was combined with the anastomosis clip, and then the wheel nail was interlocked with the clamp to make the arteriovenous end mechanically everted. Then loosen the vein and artery clamp in turn, observe and confirm the good blood circulation, suture the skin and wrap it with sterile dressing.
There is no need for special treatment after operation, the success rate of operation is high, the fistula blood flow can remain relatively stable, it is not easy to be complicated with high-output heart failure for a long time, the vein will not be seriously dilated, and the appearance can satisfy patients. In addition, this method is simple to operate and easy to master, and can be carried out in units at all levels.
However, the Qin-round nail method can only do end-to-end anastomosis, which limits its application to some extent.
4. What self-care should patients with arteriovenous fistula do?
Patients with arteriovenous fistula should take care of themselves: (1) Understand the importance of arteriovenous fistula to life, attach importance to it subjectively, and actively cooperate with medical staff.
(2) Keep the skin of the ostomy side arm clean, and thoroughly clean the ostomy side arm with soapy water before each dialysis. (3) Avoid contact with water at the puncture site on the day of dialysis, and cover it with sterile dressing for more than 4 hours to prevent infection.
If there is a hematoma at the puncture site of the table, it can be compressed to stop bleeding, and it can be cold-compressed with an ice pack. After 24 hours, hot compress can be applied with Hirudoid to reduce swelling and internal fistula. If there is induration, Hirudoid can be applied externally twice a day, each time 15 minutes. (4) The arm on the stoma side should not be compressed, the sleeves should be loose, and you should not wear too tight accessories.
Don't put the arm on the stoma side behind the pillow when sleeping at night, and try to avoid lying on the arm on the stoma side. Avoid placing heavy objects on the side arm of the stoma.
(5) Blood pressure, infusion, intravenous injection, blood drawing, etc. It cannot be measured on the arm on the stoma side. (6) Learn how to judge whether the arteriovenous fistula is unobstructed by yourself, that is, touch the anastomotic opening on the surgical side with your hand, and prompt patency if you detect tremor, or auscultate with a stethoscope, and prompt patency when you hear vascular noise.
If the tremor and murmur disappear and the fistula is tender or painful, you should go to the hospital in time. At the same time, the patient must be informed that the examination of arteriovenous fistula must be carried out three times a day. 4 times in order to find problems early.
(7) Properly move the arm on the stoma side and hold the rubber fitness ball for exercise. (8) In order to avoid arm trauma on the stoma side, it is best to wear wrist pads frequently to avoid bleeding.
The tightness of the wrist guard should be moderate, and the arteriovenous fistula should not be pressed too tightly to prevent the internal fistula from being blocked. Patients with aneurysms should be protected by elastic bandages to avoid further expansion and accidental rupture.
5. What is autologous arteriovenous fistula?
Long-term hemodialysis patients need to establish permanent blood access, which is the lifeline of maintenance hemodialysis patients. The establishment and maintenance of blood access directly affects the quality of life of hemodialysis patients. It includes adjacent arteriovenous fistula and vascular graft fistula. The main complications were thrombosis and pseudoaneurysm. Clinical arteriovenous fistula refers to the blood channel established by surgical anastomosis between adjacent arteriovenous. Therefore, we should pay attention to the following points when doing self-care; 1. After 48-72 hours, raise the limb on the operation side to reduce swelling; Second, you can exercise under the guidance of a doctor one week after the operation of internal fistula; Third, when there is no subcutaneous hematoma after the puncture of internal fistula, local compression should be applied to stop bleeding, and 50% magnesium sulfate solution should be used to wet compress and appropriate * * * should be used to help reduce swelling, and the tremor of internal fistula should be observed at the same time; Bring your own stethoscope to listen to the fistula murmur at any time and touch it with your hands to see if there is any tremor; Four, blood pressure measurement, blood collection, infusion should avoid the fistula side, and inform the nurse of skin allergies; Five, the use of internal fistula should avoid repeated puncture at the same puncture point to reduce the occurrence of pseudoaneurysm and prolong the service life of internal fistula; Sixth, do not apply hot compress on the day of dialysis, and apply hot compress on the next day to help repair blood vessels and reduce scar formation; Seventh, when the patients who use internal fistula for the first time are pressed to stop bleeding after dialysis, the time should be 1- 1.5 hours, not too long, and the compression should not be too tight to avoid bleeding and prevent internal fistula from blocking; Eight, if there is bleeding after opening the tourniquet, you can stretch out your index finger and middle finger and press the puncture point 15-20 minutes to replace a new band-aid to prevent infection at the puncture point; 9. Prepare wrist protector to protect internal fistula during non-dialysis, prevent traumatic hemorrhage and inhibit pseudoaneurysm; Due to the large blood flow, the successful use of internal fistula, long-term regular puncture, false aneurysm, blood vessel swelling, wall thinning. Pay attention to skin care and apply skin care oil every day to increase the smoothness and comfort of the skin.
Another classification of permanent blood access is vascular graft fistula, whose characteristics and self-care are similar to those of autogenous fistula. However, due to the serious injury to subcutaneous tissue, long limb recovery time, serious swelling and easy infection caused by artificial tube implantation, patients should raise the upper limb on the surgical side after operation to help reduce swelling. Listen to vascular murmurs every day, and measure the limb temperature at the surgical side by hand to prevent infection and thrombosis. It is not advisable to use tourniquet to stop bleeding after puncture, and punctate compression should be used. In order to ensure the patency of blood vessels, if there is still bleeding after the compression point is opened 1-2 hours, there is no need to panic, and punctate compression should be used to stop bleeding.
6. What are the self-care measures for arteriovenous fistula?
Self-care measures for arteriovenous fistula mainly include: (1) Pay attention to the pulsation of internal fistula: touch the internal fistula with your hands in the morning, at dinner and before going to bed, or check whether the internal fistula is unobstructed with a stethoscope (when the internal fistula is normal, you can feel obvious rustling, running water or vibration); If you find that the internal fistula is silent, you should go to the hospital for treatment immediately.
(2) Keep the skin clean, wash your hands with warm water before dialysis, cut your nails short, and don't scratch the needle eye on the fistula side. (3) If local redness, pain, itching and exudation are found in the eye of the needle after the internal fistula is used, it can be stopped every 3? Four hours.
Hirudoid (polysulfonamide cream) can be used at ordinary times, which has the functions of anti-inflammation, promoting the absorption of edema and hematoma, inhibiting the formation and growth of thrombus, promoting local blood circulation, regenerating damaged tissues and quickly relieving pain. (4) After dialysis, if the blood vessels of internal fistula are found to have severe pain, accompanied by reduced tremor of internal fistula, it is suggested that there may be thrombosis of internal fistula.
You should go to the hospital in time. (5) Blood pressure measurement and blood drawing. It is not allowed to do internal fistula on limbs; Can't lift heavy objects; No pressure; Don't wear tight clothes to watch; And pay attention to the warmth of the limbs on the fistula side.
(6) Ensure blood volume and prevent dehydration.