Transplant Nephrectomy

Success rates for kidney transplantation continue to improve. Graft survival at 1 year is now 83% for all cadaver transplants done in the United States and 93% for living related transplants.9 Some programs report greater than 90% survival even for cadaver grafts, and greater than 85% survival at 2 years.1 Despite these good results, they are not yet 100%, so a percentage of patients transplanted will fail. The fate of the kidney after transplant failure is the subject of this chapter.
DIAGNOSIS
The diagnosis of a failed renal transplant is not difficult because the patients are azotemic and require dialysis. The common causes of graft failure are technical, such as arterial or venous thrombosis, and rejection, acute or chronic. Irreversible rejection can occur despite optimum immune suppression. Sometimes rejection results from the necessity to reduce or stop immune suppression to treat a life-threatening infection. Acute rejections occurring more than 1 year after the transplant are often a result of patient noncompliance with drugs. In any of these situations, patients will usually have undergone some radiologic investigation such as Doppler ultrasound or renal scan to ascertain whether there was a treatable cause for graft dysfunction. Renal biopsy is often performed once it is clear that there is no technical cause of graft dysfunction to determine the degree of acute or chronic rejection present. Once it is certain that renal failure is irreversible, immune suppression is withdrawn, chronic dialysis is reinstituted, and a decision is made as to whether or not it is necessary to remove the allograft.
INDICATIONS FOR SURGERY
Grafts failing within the first 12 months are almost always removed prophylactically regardless of the cause of graft loss and whether or not there are specific symptoms present. This is because if the graft is left in place, significant symptoms necessitating its removal will almost always occur.3 Most of these are either technical failures, which occur in the first few weeks after transplant, or acute rejection, which is manifest in the first 2 to 3 months. Those grafts failing after 12 months are left in place initially, immunosuppression is stopped, and patients are followed. Approximately 50% of these patients will develop symptoms consistent with acute rejection such as fever, malaise, graft tenderness, or gross hematuria. These symptoms can be confused with an infection and can be difficult to distinguish from rejection. onetheless, these symptoms occurring in a patient who has recently had a failed kidney transplant are usually a result of rejection, and so a prolonged workup, searching for the source of fever, is not usually necessary or productive. These symptoms can occur many months after the patient is back on dialysis and many after the transplantation, which can make the diagnosis more difficult. Sometimes proceeding with nephrectomy is the only way to distinguish the symptoms. There has been some suggestion that repeat transplants may do worse in patients who have had the primary graft removed.1 The data on this point are not absolutely convincing, although they further support the notion of doing the nephrectomy only for specific indications.
A rare indication for allograft nephrectomy is the presence of a mass lesion of the transplant kidney. We have seen this twice in approximately 1,500 transplants. The diagnosis is usually made by ultrasound done for routine evaluation of the transplant, which detects the mass, followed by CT scan and biopsy to confirm the diagnosis. This may involve lesions unintentionally transmitted from the donor or lesions arising de novo in the transplant kidney. In the early era of transplantation, nephrectomy was often required because of technical complications such as urinary fistula or graft hemorrhage, which were not lethal to the kidney but could not be repaired. This almost never occurs now.
ALTERNATIVE THERAPY
One alternative to allograft nephrectomy is watchful waiting, as described earlier. In those whose graft is lost beyond 1 year from the transplant, about half the time no symptoms occur, and the kidney shrinks and sometimes will calcify. In those chronic cases where symptoms do occur, a short course of oral steroids is sometimes given over a week or two with prednisone, 15 mg/day initially and quickly tapered. This will ameliorate symptoms and, in a rare case, may eliminate the need for nephrectomy.
Another alternative is radiologic embolization, which we have performed in a few cases. The drawbacks are having a large kidney occluded and uncertainty as to whether this would make a subsequent transplant on that side more difficult in the future. Another drawback is that it may be hard to angiographically identify the renal artery(ies) and catheterize it (them) in the small chronic kidney, which commonly has significant intimal thickening from the rejection process. One group has reported the combination of ethanol and stainless steel coil transvenous catheter ablation in 14 patients.4 Postembolization syndrome occurred in 11 of 14 patients, and one patient had an abscess develop in the graft.
SURGICAL TECHNIQUE
The patient is placed on the operating room table in the supine position. In most cases the previous transplant incision is a lower quadrant incision (Fig. 9-1). The nephrectomy incision is over that incision and extended laterally if necessary. If the transplant had been done through a midline transperitoneal incision, it may be necessary to reopen that incision and go transperitoneally to get to the kidney. When the transplant has been transperitoneal, it is often swollen and palpable in the lower abdomen, and thus, it is possible to make the incision directly over the kidney, incise the external and internal obliques, and reach the kidney capsule. Because the kidney is usually stuck to its surrounding structures, it is possible in this situation to stay extraperitoneal and remove the kidney. Routinely, in reopening a lower quadrant incision, the scars in the external and internal obliques are reincised. Once the internal oblique is incised, the kidney should be approached as laterally as possible because the peritoneum is often draped over the kidney in the line of the incision. If the peritoneum is opened and the patient is on peritoneal dialysis. this creates a problem to use the P-D catheter until the peritoneum reseals, necessitating temporary vascular access for dialysis. This is particularly problematic in children, and it is helpful to avoid this circumstance.
In cases where the kidney has rejected, it is sometimes swollen to two to three times its normal size. The kidney is palpable superficially, but the bulk of the size is hidden in the flank. This may be the situation even where there has been chronic rejection because acute rejection is often superimposed. A very long incision may not create the amount of access needed to dissect the kidney under direct vision because of the lie of the kidney in the abdomen and flank. The subcapsular approach, in addition to helping with the kidney being stuck to surrounding structures, helps with these very large kidneys because it allows the mobilization of the kidney to be done blindly and delivers the large kidney into the incision so the pedicle can be dissected under direct vision. This is not unlike the dissection of the prostate in a retropubic or suprapubic prostatectomy for BPH.
Kidneys that have been lost in the first few days after transplant for technical reasons can be removed in toto, including the whole capsule, because these kidneys are not usually stuck to the surrounding tissues. Kidneys that have undergone rejection are usually stuck to the pelvic side wall, iliac vessels, and peritoneum. Attempts to remove these extracapsularly can result in injury to vessels or bowel in addition to being very difficult to do.6 A subcapsular approach simplifies the operation considerably, reducing risk of damage to adjacent structures.7 The renal vessels are ligated well into the hilum.
After the internal and external obliques are opened, the surface of the kidney can be balloted and often has a bluish tint. A tiny incision in the capsule is made with the knife, confirming the presence of renal parenchyma (Fig. 9-2). The Metzenbaum scissors are used to dissect bluntly under the capsule and enlarge the capsulotomy. A finger sliding under the capsule should meet a plane that dissects easily (Fig. 9-3). An exception is the rare circumstance where the kidney is small and partly calcified, where the subcapsular plane may be quite difficult to appreciate. In the more usual circumstance, the plane between capsule and parenchyma is extended around the entire kidney except the hilum, and the kidney is delivered into the wound. It may be necessary to extend the fascial incisions to allow this depending on the size of the kidney. The kidney will now be tethered by the vessels and the ureter. Care must be taken not to avulse these in delivering the kidney into the wound.
The peritoneum can be entered here, so it is best to make this incision close to the renal parenchyma. The other advantage is that ligating the vessels well into the hilum minimizes the risk of damage to the iliac artery. A theoretical disadvantage to this approach is that donor material is left in situ. Blowout of this remnant is a possibility but appears to occur only if the suture line itself becomes infected.8 Therefore, leaving this material in place usually causes no problem. The only other drawback is that if a third transplant is ever required on that side, it may be necessary to dissect this scar out at the time of the transplant. The potential problems that this presents are outweighed by the complexity of the nephrectomy and risk of trying to control the proximal and distal iliac artery and vein in the presence of a large, friable failed allograft and can sometimes be avoided by going higher on the vessels, to the common iliacs or aorta and vena cava.
The hilar structures may be densely adherent to one another, but it is usually possible to dissect arteries, veins, and ureters free for individual ligation (Fig. 9-5). It may be possible to obtain only enough length to handle the proximal vessels without ligating the kidney side. A finger over the kidney side may be sufficient until all the vessels have been ligated. Ligation plus suture ligation with 2-0 or 3-0 cardiovasculars wedged-on sutures provides security that there will be no major bleeding postoperatively. Silk, Prolene, or some other nonabsorbable suture can be used. The vessels themselves are often friable, and care must be taken not to saw through them. Occasionally a vessel is torn flush with the dense scar at the base of the kidney overlying the iliac artery or vein, which can not be seen. A figure-of-eight stitch can control it, but care must be taken not to pass the needle too deeply into the scar because the iliac vessels may be very superficial.
Once all the hilar structures have been ligated, hemostasis of the capsule must be obtained. This can be done by using the flat part of the electrocautery or an argon-beam coagulator. The entire capsular surface should be inspected. The unacceptable alternative, unless it is absolutely impossible to obtain a dry field, is to drain the space, which runs the risk of potentiating infection of the space, even if a closed drain is used. Spray thrombin can be liberally applied after coagulation. Care should be taken not to rub off the carefully obtained surface hemostasis. Antibiotic irrigation is carried out, although the evidence that this prevents infection in this situation is lacking. The wound is closed in one or two layers, depending on what is possible. I prefer interrupted 2-0 Prolene, but absorbable and running sutures are possible. Usually there is no value in specifically closing the remaining renal capsule.
OUTCOMES
Complications

Complications reported in earlier series included major perioperative bleeding, wound infections, and intraoperative injury to adjacent structures.5 The incidence of hemorrhage following transplant nephrectomy is 5% to 6%.2 Routine use of the subcapsular approach can reduce these complications to less than 1%.6
The other type of complication is less related to the operation than it is to immune suppression. Even though patients undergoing allograft nephrectomy have had their immune suppression stopped before the nephrectomy, it may have been only a few days before. The sequelae of immune oversuppression may take days or weeks to manifest themselves. In the UCLA series, two perioperative deaths were from B-cell lymphoma related to immune oversuppression. Persistent fever after nephrectomy should be carefully evaluated.
Results
Transplant nephrectomy can be performed with minimal morbidity, though it can be extremely challenging in the postrejection setting. The issue of the value of transplant nephrectomy to reduce the possibility of rejection of subsequent renal allografts remains controversial.

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