Reducing cross-clamping duration in aortoiliac reconstruction after renal transplantation. A case report

Aortoiliac Aneurysm Repair in Kidney Transplant Recipients

A potential problem during endovascular aortic aneurysm repair (EVAR) or open repair in renal allograft patients is ischemia of the transplanted kidney. In this study, kidney transplant patients who underwent aortic aneurysm repair in our institution were added to similar cases extracted from the literature to represent the basis of this work. Comparisons between patients treated with open surgery versus EVAR were performed in terms of renal function. In the EVAR group, most aneurysms were infrarenal, and 84% were treated with modular bifurcated devices. Protective kidney allograft perfusion measures were not used. The pre- and postoperative Cr was 1.69 and 1.73 mg/dL, respectively (P = .412). All EVAR patients had good outcomes. Complications included 8 endoleaks and 1 limb ischemia case. Three patients died from aortic repair-unrelated reasons. In the open group, the pre-and postoperative Cr was 1.45 and 1.37 mg/dL, respectively (P = .055). Most cases were infrarenal and mostly treated by aortobiiliac bypasses. In 16%, no adjuvant allograft perfusion was provided. In the rest, temporary axillofemoral bypasses were used most often. Most outcomes were favorable (57%). Reported procedural-related complications included arterial embolism, wound infection, and pneumonia. Deaths were reported in 5 occasions (none allograft failure dependent). No differences in Cr between EVAR and open techniques (P = .13) were seen. Aneurysm repair in kidney transplant recipients is associated with excellent renal preservation. Adverse outcomes were all allograft failure independent in both groups. EVAR without special allograft protection measures seems to be equally effective as open surgery with or without adjuvant kidney transplant perfusion.

Renal Function after Elective Infrarenal Aortic Aneurysm Repair in Patients with Pelvic Kidneys

Pelvic kidneys complicate aortic reconstructions because of increased risk of renal ischemia. Strategies for protection include shunting, cooling, and reliance on collaterals. A review identified two congenital pelvic kidney (not solitary) and five transplanted kidney patients who underwent elective abdominal aortic aneurysm repair. For congenital pelvic kidneys, topical cooling was used in one patient while no preservation was performed for the other patient. Three transplanted kidney patients were shunted, and one had endovascular repair. Postoperative creatinine values were compared to preoperative values. The two congenital pelvic kidney patients had no significant elevation of creatinine postoperatively. The transplanted kidney patient who underwent endovascular repair had no increase in creatinine postoperatively. All transplanted kidney patients who had open repair had significant but transient increase in creatinine postoperatively. Three patients who were shunted intraoperatively had normalization of creatinine. The patient who had persistent elevation of creatinine at discharge was not shunted. Aortorenal shunting or endovascular repair in transplanted pelvic kidney patients maintains renal function. For patients with congenital pelvic kidneys and adequate collaterals, cooling and collateral perfusion is usually sufficient. Though experience is limited, endovascular repair is likely to be superior to open repair in minimizing renal ischemia.

Abdominal Aortic Aneurysm Repair in Kidney Transplant Recipients

Renal transplant recipients currently survive many years with a consequent increase in the risk of presentation with vascular diseases. So aortic reconstruction in transplant patients has been increasingly reported the most common procedures involving abdominal aorta aneurysms (AAAs). The most important problem during the operation is ischemic injury to the transplanted kidney during aortic clamping. Protection for the grafted kidney from ischemic or reperfusion injury may be achieved by permanent or temporary axillo-femoral, femoro-femoral, aorto-iliac bypass, cold perfusion, local cold preservation, or autotransplantation. Some authors have reported protection of the transplanted kidney function without any other procedures. We had experience with four AAA cases in kidney transplant patients, including two cases of direct reconstruction of the AAA without any other surgical protection, one autotransplantation, and one AAA excision with using temporary aortofemoral bypass with good results. Herein, we report two cases of successful AAA excision without a surgical procedure for graft protection.

Aortic reconstruction in patients with functioning renal allografts

Patients with functioning renal allografts requiring aortic reconstruction pose a considerable challenge to the vascular surgeon. A variety of strategies for renal allograft preservation during intervention have been described including hypothermia, indwelling shunts, cold renal perfusion, axillofemoral bypass, and endovascular stent-grafting. Reported here are two cases of successful aortic reconstruction utilizing standard open surgical techniques designed simply to minimize warm renal ischemia. The first case was that of a 55 year-old patient with a functional renal allograft originating from the right external iliac artery, who presented acutely with large symptomatic aortic and bilateral iliac artery aneurysms. He was treated with aorto-right femoral/left iliac bypass grafting. The right femoral anastomosis was performed first so that warm renal ischemia was limited to the 34 min required to perform the proximal end-to-end aortic anastomosis. The second case was that of a 44-year-old patient also with a transplanted kidney originating from the right external iliac artery. He presented with worsening hypertension, decreasing renal function, claudication, and severe aortoiliac occlusive disease. He was treated with aorto-left femoral bypass grafting via a retroperitoneal approach, followed by femorofemoral crossover bypass for retrograde perfusion of the kidney (total warm ischemia time 20 min). Both patients recovered uneventfully without a decrement in renal function and remain well on follow-up. It is concluded that standard open surgery without adjunctive shunts or bypasses remains a viable treatment option for these patients, provided warm renal ischemia can be minimized.

Abdominal aortic aneurysm repair in patients with renal allografts

Aortic reconstruction is being reported in an increasing number of patients after renal transplantation as a result of improved renal graft survival and life expectancy. Aortic surgery in these patients places the pelvic allograft at risk for ischemic damage. We present two separate modalities that have been successfully used in protecting the renal transplant from prolonged warm ischemia during abdominal aortic aneurysm (AAA) repair in two cases. One technique involves an aortofemoral shunt using the perirenal aorta for proximal cannulation and the other technique utilizes an indwelling shunt through the prosthetic graft. Both patients had an uneventful recovery with no evidence of renal dysfunction and their renal function has been stable on long-term follow-up. These cases illustrate two useful alternatives in providing pulsatile perfusion to a transplanted kidney in the iliac fossa during AAA repair. They have been used successfully as simpler alternatives to temporary axillofemoral bypass or extracorporeal pump oxygenation in preventing postoperative renal dysfunction.