Intraoperative coil embolization reduces transplant nephrectomy transfusion requirement

Transplant Nephrectomy: Current Concepts

Kidney transplantation is the gold standard treatment option for patients with endstage kidney disease. As the number of waitlisted patients increases, the gap between supply and demand for suitable donor kidneys keeps widening. The adoption of novel strategies that expand the donor pool has attenuated this issue to a certain degree, and this has led to a progressive increase in the number of annual transplants performed. As transplanted kidneys have a finite lifespan, there is a reciprocal rise in the number of patients who return to dialysis once their allograft fails. The clinicians involved in the management of such patients are left with the problem of managing the nonfunctioning allograft. The decision to undertake transplant nephrectomy (TN) in these patients is not straightforward. Allograft nephrectomy is a procedure that is associated with significant morbidity and mortality. It will have implications for the outcomes of the subsequent transplant. In this review, we aimed to compressively discuss the indications, techniques, and outcomes of TN, which is an integral component of the management of a failing allograft.

Pearls and Pitfalls in Pediatric Kidney Transplantation After 5 Decades

Worldwide, over 1,300 pediatric kidney transplantations are performed every year. Since the first transplantation in 1959, healthcare has evolved dramatically. Pre-emptive transplantations with grafts from living donors have become more common. Despite a subsequent improvement in graft survival, there are still challenges to face. This study attempts to summarize how our understanding of pediatric kidney transplantation has developed and improved since its beginnings, whilst also highlighting those areas where future research should concentrate in order to help resolve as yet unanswered questions. Existing literature was compared to our own data of 411 single-center pediatric kidney transplantations between 1968 and 2020, in order to find discrepancies and allow identification of future challenges. Important issues for future care are innovations in immunosuppressive medication, improving medication adherence, careful donor selection with regard to characteristics of both donor and recipient, improvement of surgical techniques and increased attention for lower urinary tract dysfunction and voiding behavior in all patients.

Improving Outcomes after Allograft Nephrectomy through Use of Preoperative Angiographic Kidney Embolization

BACKGROUND

Allograft nephrectomy (AN) has been associated with considerable perioperative morbidity. We aimed to determine if preoperative angiographic kidney embolization (PAKE) to induce graft thrombosis before AN improves outcomes.

STUDY DESIGN

We reviewed adult kidney transplant alone patients who underwent AN at a single center from 2002 to 2020 and compared perioperative outcomes for patients with and without PAKE.

RESULTS

Eighty patients underwent AN, including 54 (67.5%) with PAKE before AN and 26 (32.5%) with AN alone. PAKE was associated with significantly reduced blood loss (PAKE: mean 266 ± 292 mL vs AN alone: 495 ± 689 mL; p = 0.04) and reduced transfusion requirements (PAKE: mean 0.5 ± 0.8 packed red blood cell units vs AN alone: 1.6 ± 2.6 units; p = 0.004) despite similar preoperative hemoglobin levels. Mean operating time (PAKE: 142 ± 43 minutes vs AN alone: 202 ± 111 minutes; p = 0.001) and length of hospital stay (PAKE: 4.3 ± 2.0 days vs AN alone: 9.3 ± 9.4 days; p = 0.0003) also favored PAKE, as did the surgical complication rate (PAKE: 6/54 [11%] vs AN alone: 9/26 [35%], p = 0.02). Long-term patient survival after AN was comparable in both groups.

CONCLUSIONS

PAKE was associated with lower intraoperative blood loss, fewer transfusions, reduced operating time, shorter length of stay, and fewer surgical complications compared with AN alone at our center.

The Failing Kidney Transplant Allograft. Transplant Nephrectomy: Current State-of-the-Art

PURPOSE OF REVIEW

This review provides a critical literature overview of the risks and benefits of transplantectomy in patients with a failed allograft. Additionally, it offers a summary of related problems, primarily alloantibody sensitization in the event of nephrectomy and immunosuppression weaning.

RECENT FINDINGS

Transplant nephrectomy has high morbidity and mortality rates. The morbidity of transplant nephrectomy (4.3 to 82%) is mostly due to hemorrhage or infection. Mortality rates range from 1.2 to 39%, and most are due to sepsis. Transvascular graft embolization has been described as a less invasive alternative technique for the management of symptomatic graft rejection, with minimal complications compared with transplantectomy. The number of patients with a failed allograft returning to dialysis is increasing. The role of allograft nephrectomy in the management of asymptomatic transplant failure is still controversial and up today continues to depend on the usual clinical practice of each institution. The less invasive transvascular embolization could have applicability in asymptomatic patients with the obvious lower morbidity and mortality rate.

Graft nephrectomy in children

Kidney transplantation is recognised as the gold standard treatment of end-stage renal disease in most children, with excellent graft survival rates. When graft failure occurs, renal transplant recipients (RTRs) have the option of removal of the transplant (graft nephrectomy [GN]), or leaving the failed transplant in situ. The aims of this review are to discuss the indications for GN, surgical techniques, outcomes after GN (including risks of allosensitisation and the impact on subsequent transplants), and the possible role of routine GN in the asymptomatic RTR with a failed renal allograft. Literature in both the pediatric and adult renal transplant fields is reviewed. We also discuss how future research in this area could advance our knowledge of which patients to select for GN, and the most appropriate surgical approach.

Use of preoperative embolization prior to Transplant nephrectomy

Introduction

After a failed transplant, management of a non-functional graft with pain or recurrent infections can be challenging. Transplant nephrectomy (TN) can be a morbid procedure with the potential for significant blood loss. Embolization of the renal artery alone has been proposed as a method of reducing complications from an in vivo failed kidney transplant. While this does yield less morbidity, it may not address an infected graft or refractory hematuria or rejection. We elected to begin preoperative embolization to assess if this would help decrease the blood loss and transfusion rate associated with TN.

Materials and Methods

We performed a retrospective analysis of all patients who underwent non-emergent TN at our institution. Patients who had functioning grafts that later failed were included in analysis. TN was performed for recurrent infections, pain or hematuria. We evaluated for blood loss (EBL) during TN, transfusion rate and length of hospital stay.

Results

A total of 16 patients were identified. Nine had preoperative embolization or no blood flow to the graft prior to TN. The remaining 7 did not have preoperative embolization. The shortest time from transplant to TN was 8 months and the longest 18 years with an average of 6.3 years. Average EBL for the embolized patients (ETN) was 143.9cc compared to 621.4cc in the non-embolized (NETN) group (p=0.041). Average number of units of blood transfused was 0.44 in the ETN with only 3/9 patients requiring transfusion. The NETN patients had average of 1.29 units transfused with 5/7 requiring transfusion. The length of stay was longer for the ETN (5.4 days) compared to 3.9 in the NETN. No intraoperative complications were seen in either group and only one patient had a postoperative ileus in the NETN.

Conclusion

Embolization prior to TN significantly decreases the EBL but does not significantly decrease transfusion rate. However, patients do require a significantly longer hospitalization with embolization due to the time needed for embolization. Larger studies are needed to determine if embolization before transplant nephrectomy reduces the transfusion rates and overall complications.

Renal artery embolization-indications, technical approaches and outcomes

Owing to improvements in catheters and embolic agents, renal artery embolization (RAE) is increasingly used to treat nephrological and urological disease. RAE has become a useful adjunct to medical resuscitation in severe penetrating, iatrogenic or blunt renal traumatisms with active bleeding, and might avoid surgical intervention, particularly among patients that are haemodynamically stable. The role of RAE in pre-operative or palliative management of advanced malignant renal tumours remains debated; however, RAE is recommended as a first-line therapy for bleeding angiomyolipomas and can be used as a preventative treatment for angiomyolipomas at risk of bleeding. RAE represents an alternative to nephrectomy in various medical conditions, including severe uncontrolled hypertension among patients with end-stage renal disease, renal graft intolerance syndrome or autosomal dominant polycystic kidney disease. RAE is increasingly used to treat renal artery aneurysms or symptomatic renal arteriovenous malformations, with a low complication rate as compared with surgical alternatives. This Review highlights the potential use of RAE as an adjunct in the management of renal disease. We first compare and contrast the technical approaches of RAE associated with the various available embolization agents and then discuss the complications associated with RAE and alternative procedures.

Transplant nephrectomy

About 10% of all renal allografts fail during the first year of transplantation and thereafter approximately 3%-5% yearly. Given that approximately 69 400 renal transplants are performed worldwide annually, the number of patients returning to dialysis following allograft failure is increasing. A failed transplant kidney, whether maintained by low dose immunosuppression or not, elicits an inflammatory response and is associated with increased morbidity and mortality. The risk for transplant nephrectomy (TN) is increased in patients who experienced multiple acute rejections prior to graft failure, develop chronic graft intolerance, sepsis, vascular complications and early graft failure. TN for late graft failure is associated with greater morbidity and mortality, bleeding being the leading cause of morbidity and infection the main cause of mortality. TN appears to be beneficial for survival on dialysis but detrimental to the outcome of subsequent transplantation by virtue of increased level of antibodies to mismatched antigens, increased rate of primary non function and delayed graft function. Many of the studies are characterized by a retrospective and univariate analysis of small numbers of patients. The lack of randomization in many studies introduced a selection bias and conclusions drawn from such studies should be applied with caution. Pending a randomised controlled trial on the role of TN in the management of transplant failure patients, it is prudent to remove failed symptomatic allografts and all grafts failing within 3 mo of transplantation, monitor inflammatory markers in patients with retained failed allografts and remove the allograft in the event of a significant increase in levels.