kidney transplant

Kidney transplantation usually includes both autologous and allogeneic transplantation. In autologous kidney transplantation, the kidney is cut and then implanted in the same body, and the donor and the recipient are the same person. For example, when the initial portion of the renal artery is narrow, the kidney can be moved to the armpit. The same kind of kidney transplantation is a transplant between different individuals of a species. The latter have varying degrees of immune confrontation, leading to rejection of the transplanted kidney. Indication 1. The main indication for autologous kidney transplantation is that the beginning of the renal artery has irreparable lesions. When the complex intrarenal stones or deformities are difficult to solve by general methods, the kidneys can be repaired and then transplanted to the armpits (ie, the bench surgery). 2. The same kidney transplant is suitable for every patient with irreversible kidney disease and chronic renal failure. Common are glomerulonephritis, interstitial nephritis, pyelonephritis, renal vascular sclerosis and polycystic kidney disease. In addition, there are cases of kidney or isolated kidney loss caused by trauma. Contraindications Diseases associated with renal failure should be classified as contraindications for kidney transplantation. 1. When kidney disease is a local manifestation caused by a systemic disease, kidney transplantation cannot be considered because the disease will spread to the transplanted kidney. Such as amyloidosis, nodular arteritis and diffuse vasculitis. 2. Patients with severe systemic infections, tuberculosis, peptic ulcers and malignant tumors cannot be considered for kidney transplantation. The disease will rapidly deteriorate as a result of the application of immunosuppressants and steroids after transplantation. Preoperative preparation 1. Supportive dialysis treatment, the patient's systemic condition is significantly improved, renal function, water and electricity balance and acid-base balance are at or near normal, and the heart condition is good. 2. Patients with more persistent hypertension or residual kidney disease should remove the bilateral kidneys of the recipient before surgery to control blood pressure or prevent infection. Waiting for about 1 week, the blood pressure is reduced before transplanting, in order to facilitate the function of transplantation. 3. Remove and control various infectious lesions in the body, such as athlete's foot, tonsillitis and local skin diseases. 4. Blood biochemistry and special examination before general surgery. Surgical procedure a) extraction of the kidney There is no significant difference between the kidneys of the donor and the general nephrectomy. The main difference is that you need to be very careful during surgery. Surgery requires no damage to the cut kidney and preserves the length of the arteries and veins as much as possible without affecting the blood supply to the ureter. Nephrectomy for living donors The living donor can predict the anatomical distribution of the renal blood vessels by angiography before surgery, and perform nephrectomy at the same time as the transplantation operation, which can greatly shorten the ischemic time of the transplanted kidney. Generally, the left kidney is preferred. Because the left renal vein is relatively long, the left kidney can be turned over and transplanted into the right axilla, so that the vein is behind the artery, which is convenient for anastomosis. If the donor is a young woman, the right kidney should be taken, because there is more chance of complications in the right urinary tract during pregnancy, and the function of retaining the kidney can be guaranteed after the right kidney. If other conditions are similar, the kidney of a single renal artery should be taken. 1. Extraction of the left kidney (1) Incision: The incision should be larger to allow satisfactory exposure of the kidney and kidney pedicle. The location of the incision depends on the location of the kidney and the starting point of the renal artery. Commonly used is the twelfth rib or the eleventh intercostal incision. (2) Free kidney: Cut the skin, subcutaneous tissue, muscle and periorbital fascia, separate the perirenal adipose tissue, and use electrocoagulation to stop the small vessels of the renal capsule. The kidney is separated first, and the upper pole of the kidney is separated to make the kidney easy to move down. Special care should be taken to protect the ureter's blood supply when separating the ureters, especially those that are easily broken. (3) Anatomy of the renal pedicle vessels: continue to separate the ureter to the renal pelvis, separate the inferior pole, and then expose the vein. The vein is in front, so it is divided in front and then turned to the inside to the beginning of the superior mesenteric artery. The main branch of the renal vein is the adrenal vein, and the lower part is the spermatic cord (ovary) vein. The kidney is attached to the renal vein, and the ligation is performed separately. The lumbar ascending vein can be found at the posterior edge of the renal vein. If it exists, it should be ligated. Cut off. It is rare for the renal vein to be divided into two, often at the beginning of the superior mesenteric artery. The kidneys are then separated and the kidneys are turned forward to dissect the renal arteries and trace to the starting point where the aorta is separated. There are few other branches besides the adrenal artery requiring severing ligation. During anatomy, the lymphatic vessels and nerves of the kidney can be cut by electrocautery; in order to prevent renal artery spasm and renal ischemia, it is important to avoid pulling the kidney or renal artery, and procaine infiltration around the renal artery can prevent sputum. The anatomy is also convenient. The anatomy of the renal pedicle should be such that only the arteries, veins, and ureters remain attached to the body. (4) Separation and severing of the ureter: The kidney cannot be cut before the surgical transplantation group is ready. The ureter is mostly cut off at the level of the iliac vessels and is ready for use as a ureteral bladder anastomosis. (5) Cut the kidney: Clamp the cut at the beginning of the renal artery. Lifting the kidneys makes it easier to treat the veins. Close to the arterial end of the kidney, there is no need to clamp the pliers because the possibility of a gas plug is minimal. If there are multiple branches of the renal artery, they should be ligated and cut. The renal vein is clamped with a de bakey forceps. When cutting, try to be as close to the inner side as possible to keep the renal veins longer to match. The cut kidneys were immediately flushed into the perfusion group. Firmly ligature and sew the renal blood vessel stump. When the incision is sutured, the drainage may or may not be placed. 2. The technique of extracting the right kidney is roughly the same as that of the left kidney. (1) Incision: The same is used for the left lumbar incision or the transabdominal midline incision, which is beneficial for revealing the renal vascular end. (2) Anatomy of the renal blood vessels: before the kidney is separated. The anterior portion of the renal pedicle is the renal vein, which is separated at the junction with the inferior vena cava, and the separated inferior vena cava is lifted with a gauze band. The right renal vein is very short and there is no large branch recirculation; the right kidney has two renal veins more common, and special attention should be paid when separating. The renal artery is located on the posterior side of the vein and should be separated from the distal end or from the starting point to the other end. When the renal artery behind the inferior vena cava is treated, the inferior vena cava can be pulled apart by a gauze, which is easy to expose. (3) Anatomical ureter is the same as the left side. (4) Freeing and cutting the kidney: The release of the right kidney should be carried out in the kidney socket. Do not lift it out of the incision to prevent the blood vessels, especially the arteries, from twisting. In order to keep the renal vein as long as possible, a vascular clamp can be placed on the side of the inferior vena cava, a small cavity wall is cut together with the renal vein, and the inferior vena cava incision is properly sutured. If the two renal veins are close together, the wall of the cut vena cava should include two openings for the renal vein. If the two veins are far apart, they should be cut off separately. If one of the veins is less than 5 mm in diameter, it can be ligated, because the veins in the kidney communicate with each other. The rest are on the left side. Corpus nephrectomy The cadaveric kidney is usually taken from the donor after the brain has died, and both kidneys are removed. Abdominal aorta angiography cannot be performed in advance. Therefore, it is impossible to predict any anatomical abnormalities. The surgeon's surgery must be performed when the kidney is clearly available. 1. Position the body on the back and raise it at the 12th rib. 2. Three kinds of incisions. A horizontal incision across the abdomen is made at 2 to 3 transverse fingers on the umbilicus, and the ends should be offset to the 12th rib tip; or a straight incision from the xiphoid to the pubis, using a rib retractor; or a large abdomen incision. The latter is the best and is widely used. 3. Pull the left side of the spleen to reveal the left kidney. If the left kidney is large and the position is high, the spleen and pancreas should be pulled apart. The anatomical steps are the same as for living donors. However, the aorta and renal pedicle should be ascertained as soon as possible to determine if the two kidneys are suitable for transplantation. 4. The duodenum and pancreas are pulled inward to the midline to first reveal the starting point of the abdominal and right renal arteries. Pulling the colonic hepatic curvature helps to separate the inferior pole and ureter. After the kidneys on both sides are exposed, the kidneys and renal blood vessels can be separated as the living donor. In order to quickly dissect the right renal artery after the inferior vena cava, two pliers can be placed in the inferior vena cava below the level of the renal vein, and the inferior vena cava can be cut between the two pliers. 5. An abnormality in the treatment of blood vessels and ureters can lead to changes in the surgical plan. If there is two arteries in one kidney, the contralateral kidney with only one artery should be separated first. If the starting points of the two arteries are connected together, the side wall of the aorta can be clamped, and the part containing the two renal artery openings will be separated. The arterial wall is cut together. If the starting points of the two renal arteries are far apart, they should be cut off separately. In the case of an independent and small diameter artery, in addition to a small supply range, it should not be rashly ligated, and the injured person should be matched. The abnormality of the vein is easier to handle and is basically the same as that of the living body. The ureteral malformation should be shaped. If the double ureter is connected in the lower segment, it should be cut below the joint. When the kidney is deformed, the transplant team should be notified of the details immediately in order to revise the surgical plan. (two) kidney transplantation Because uremia patients are treated with immunosuppressive agents, the healing ability and defense ability are very poor, so pay special attention to the following points. 1 In order to prevent the occurrence of hematoma, it is necessary to strictly stop bleeding to avoid concurrent infection or compression of the transplant. However, such patients have a tendency to hemorrhage and it is difficult to stop bleeding. 2 Strict aseptic operation must be performed in all aspects of the operation. The source of the infection is often caused by a large incision of the bladder when the ureter is transplanted into the bladder. Therefore, this kind of incision should be avoided as much as possible. The kidney can be transplanted in situ, usually on the left side. However, because the postoperative graft is not easy to observe, in case of surgical complications and re-operation is more difficult, the method of transplanting the donor kidney into the right armpit is generally adopted. This method is simple and straightforward, and easy to observe after surgery. The palpation of the kidney, the estimation of the volume change, and the biopsy are easier. Once the complications occur, there is no difficulty in reoperation. The technique of transplantation into the left axilla is the same as that of the right axilla, but it may be difficult. One is because the sigmoid colon and its mesenteric membrane are not easily pulled apart, and the second is because the blood vessels, especially the common iliac vein, are deep in the pelvis. When vascular anastomosis, especially venous anastomosis, it is more difficult. Therefore, the left axilla is used only for the second transplant after the right graft has failed. However, there is also a practice of transplanting the right kidney to the right axilla. Kidney transplantation can be roughly divided into three steps, namely, preparation of the renal socket and recipient blood vessels, reconstruction of the blood supply to the transplanted kidney, and restoration of continuity of the urinary tract. The conventional steps now transplanted into the right armpit are described below. 1. Incision: The right axillary area is an oblique incision. 2. Expose the iliac vessels: cut the skin, subcutaneous tissue, and abdominal wall muscles in turn, and expose them in the peritoneum. Pay attention to carefully stop bleeding. The ureter and the peritoneum are pulled apart, the external iliac artery is found, lifted with a ribbon, and the entire length is separated to expose the vein in front of or behind it. The anatomy continued along the common iliac artery, and the entire length of the internal iliac artery was finally separated, and the small branch behind it was ligated. Make the separation section of sufficient length. The trunk of the artery is pulled inwardly to expose and separate the vein fixed to the underlying pelvic wall. From the beginning of the external iliac vein to the beginning of the inferior vena cava, the entire segment is separated from the bottom up. The blood vessels are surrounded by a dense lymphatic network. During the separation, the lymphatic vessels are electrocauterized or ligated to prevent lymphatic leakage or secondary lymphatic cysts. 3. Preparation of anastomotic vessels: After the internal iliac artery and the common iliac vein are completely separated, the end of the internal iliac artery is ligated, the starting end is clamped with a blood vessel clamp, and the ligature is cut tightly. The arterial lumen was flushed with heparinized saline to exfoliate the adventitial membrane at the end. In addition, the vein was clamped with a satinski forceps to block the broad outer side. The vascular anastomosis can be performed. 4. Venous anastomosis: Move the irrigated frozen kidney to the operating table. Turn the left kidney over so that it is facing forward. If you use the right kidney, keep it in place, so that the kidney is in the most natural position. Then choose the site where the renal vein and the iliac vein are most likely to meet, and make a venous anastomosis. The site of the venous anastomosis is deep, so it needs to be done first. In the selected part of the iliac vein, according to the diameter of the end of the renal vein, a small elliptical vein wall of similar size is cut. An end-to-side anastomosis of the renal vein and the iliac vein. First, a needle was sutured at each of the 4-0 single nylon threads at the two corners of the anastomosis. The posterior wall of the anastomosis was sutured continuously in the venous cavity. The anterior wall was sutured outside the blood vessel and the thread was struck outside. After the venous anastomosis is completed, a blalock forceps can be placed on the renal vein to remove the satinski forceps clamped on the iliac vein to restore venous return from the lower extremities. 5. Arterial anastomosis: Carefully dilate the renal artery stump and incline to enlarge the anastomosis. Most of the internal iliac artery is located on the anterior side of the external iliac artery. It is not difficult to rotate the distal end outward due to the position of the starting point and its length. The recipient's arterial port diameter is often larger than that of the renal artery. However, after the renal artery is beveled, it is similar to the diameter of the internal iliac artery, and the blood vessel after the anastomosis can be curved to facilitate blood circulation. Use a non-damaged suture in the end for a simple continuous suture, or a continuous suture in two and a half circles. Rinse with heparin saline before the anastomosis is completed to remove air bubbles and prevent intranetal air embolism. 6. Connect the blood flow supply: first release the forceps of the clamp vein to prevent the intra-renal tension from being too high, and then release the forceps clamped on the internal iliac artery, but the blood vessel clip clamped on the renal artery is not removed temporarily, and the blood vessel is promoted. The residual air inside is completely eliminated. Finally, the renal artery clip is released, and the color and tension of the kidney are quickly restored. After a few seconds, the ureter begins to squirm, and in a few minutes there is urine. If the tension of the kidney is too high, you can do a renal capsule ring incision to reduce the pressure, but it is easy to cause more bleeding, so some people advocate not. 7. Rebuilding the urinary tract: There are usually two ways. (1) ureteral implantation of bladder or ureteral bladder anastomosis: this method has the effect of anti-urine countercurrent. The method is to cut in the near bottom of the bladder, and about 4 to 5 cm above the opening of the right ureter, poke a small hole in the muscle layer of the bladder wall with a hemostatic forceps. From this point, use a curved vascular clamp to the normal ureter. The direction is a submucosal tunnel of 3 to 4 cm in length. Cut the mucosa at the lower end of the tunnel. The ureter is pulled into the bladder by a small hole in the wall of the bladder and along the submucosal tunnel. Cut the excess ureter and cut the longitudinal section of the ureteral section to expand the new opening. The ureter end is then sutured intermittently with the bladder mucosa. When the ureter enters the bladder, several stitches are fixed by intermittent suture to strengthen the anastomosis. Be careful not to twist the ureter. The opening of the bladder wall and the submucosal tunnel should be looser to prevent the lower end of the ureter from being narrowed. The bladder is sutured in two or three layers and used as an indwelling catheter. The advantage of this method is that it can be applied in a variety of cases. The disadvantages are more complicated, technical operations are more difficult, and there is the possibility of contaminating the field to cause infection. In addition, due to poor blood supply to the end of the donor ureter, there is a risk of ureteral necrosis and secondary stenosis or urinary fistula. The ureter may also be narrowed in a section of the bladder wall. (2) ureteral end-to-end anastomosis: If the recipient's ureter is available, it is better to have a ureter-ureter end-to-end anastomosis. The ureter was cut at 2 to 3 cm below the junction of the ureter and renal pelvis, and the longitudinal shape of the broken end was cut to enlarge the anastomosis; the distal end of the recipient's ureter was treated the same. In order to keep the blood supply to the ureter unaffected, the separation section should be as short as possible and not peeled off from the abdominal wall. The fixed sutures were made through the ends of the anastomosis, and then sutured with a 5-0 nylon thread. This method combines the advantages of the simplest and least risk of infection, and the patient's own ureter can protect the transplanted kidney from backflow. The disadvantage is that the ipsilateral kidney must be removed.