We describe a case of polytetrafluoroethylene vascular graft interposition between the internal iliac artery and the renal artery in a live-related kidney transplant. To the best of our knowledge, we present the first case in the literature that describes the salvage of a transplant kidney using this technique.

Key words : Organ transplant, Reperfusion, Heparinization

Introduction

The increasing demand for kidney transplantation has prompted the transplant community to expand the donor pool (optn.transplant.hrsa.gov); therefore, it is important to consider every organ available, even when there are short or damaged arteries. Several techniques have been described such as an end-to-end anastomosis with the internal iliac artery, as distal as possible, or extention using autologous veins, third-party “vascular extenders” derived from deceased donor vessels, or polytetrafluoroethylene (PTFE) vascular grafts.^1-3

We describe a case of PTFE vascular graft (GORE-TEX Vascular Graft, W. L. Gore & Associates, Inc., Newark, DE, USA) interposition between the internal iliac artery and the renal artery in a live-related kidney transplant (LRKT). To the best of our knowledge, we present the first case in the literature that describes the salvage of a transplanted kidney using this technique.

Case Report

A 20-year-old Asian woman underwent a LRKT, placed in the right iliac fossa. Her medical history was noteworthy for end-stage renal disease due to IgA nephropathy, which required renal replacement therapy in 2012. She started on peritoneal dialysis and switched to hemodialysis after 6 months because of an episode of peritonitis. The donor nephrectomy carried out on her mother was uneventful and the kidney was of normal size, with single vessels (single artery and vein).

The transplant surgery used the standard technique and the vascular anastomoses were fashioned according to the Carrel technique. Of note, during dissection, the external iliac artery was found to be of small caliber and extremely fragile. At reperfusion, the kidney was not adequately perfused and the pulse of the external iliac artery distal to the anastomosis was weak. An embolectomy, with a No. 5 Fogarty catheter was inserted through a transverse arteriotomy and the iliac artery restored the flow in the external iliac artery but did not improve the perfusion of the graft. It then was decided to redo the arterial anastomosis using the internal iliac artery in an end-to-end fashion with the renal artery, and suture the defect on the external iliac artery using interrupted Prolene 6.0 sutures.

During dissection of the internal iliac artery, the kidney was explanted and flushed again at the back table. It was then retransplanted and the perfusion improved. An ultrasound scan, performed in the recovery room, showed minimal perfusion of the graft and the patient was re-explored. The kidney appeared mottled and hypoperfused. The arterial anastomosis appeared widely patent, and the perfusion improved after repositioning the kidney in the iliac fossa.

A postoperative scan after closing of the abdominal wall showed global renal perfusion with persistent forward diastolic flow, normal flow within the transplant artery, and vein and resistive indices ranging from 0.60 to 0.66 (Figure 1). On day 1, the patient became oliguric and a computed tomography angiogram showed tight stenosis at the arterial anastomosis, with poor, patchy perfusion of the transplant. A decision to re-explore the patient was made. Because the short length of both the renal artery and internal iliac artery, the decision to interpose a PTFE graft between the renal and the internal iliac artery was made. Therefore, a 4-cm PTFE interposition graft (6 mm of diameter) was used, and 2 end-to-end anastomoses were fashioned on each side of the graft with interrupted Prolene 6.0 sutures (Figure 2). Warm ischemia time was approximately 50 minutes.

Both intra- and immediately postoperative ultrasound scans showed good global perfusion of the transplant graft (Figure 3). In the postoperative period the patient received intravenous heparin for 10 days (according to our protocol—initial dosage of 100 U/h, then adjusted), then switched to oral antiaggregation.

The postoperative period was complicated by delayed graft function, and superficial site infection managed conservatively. At 6 months follow-up, the patient is asymptomatic with stable graft function (serum creatinine, 150 mmol/L).

Discussion

The use of PTFE grafts in transplantation is limited to a few case reports.^1-5 Kamel and associates described 3 cases of successful renal vessel elongation (2 renal veins and 1 renal artery) using PTFE grafts, anastomosed to the external iliac vein and artery.² Blacklock and associates also described a case of kidney autotransplant for treatment of loin groin haematuria syndrome with the use of a PTFE graft for the arterial anastomosis.³ Polytetrafluoroethylene interposition grafts also have been successfully used in liver transplants.^4,5

Our experience is the first ever described case involving the internal iliac artery. Unfortunately, the use of the internal iliac artery, taken as distally as possible, was not sufficient to position the kidney comfortably in the iliac fossa. It adds an additional case in favor to the use of PTFE graft in reconstructing donor renal vessels, when other options, namely autologous vein graft or deceased donor vascular grafts, are not available at transplant.

We decided not to use an autologous vein graft to keep the warm ischaemic time below 1 hour, minimizing the insult to the graft. We did not experience any technical problem or complication in the described case.

In contrast to Kamel and associates, we administered antiaggregation to our patient during the procedure and in the long term. There is no clear evidence in the literature regarding the use of systemic heparin; some authors report an increased risk of bleeding,² others suggest the use of antiaggregation.⁶

Most of the long-term data on the use of PTFE vascular grafts originates from its use in lower limb revascularization.⁶ These grafts tend be long and with slow blood flow. Polytetrafluoroethylene vascular grafts used during kidney transplant are short in length and with high blood flow and consequently may have better long-term results than PTFE grafts used in treating lower limb ischemia. Studies comparing long-term results of biologic source vs prosthetic vascular grafts in kidney transplant are needed.

In cases of damaged or shortened donor renal vessels the transplant surgeon faces a technical challenge and often limited options are available. In these cases, the use of PTFE vascular interposition grafts provide a simple and technically feasible solution.

References:

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