Immediate retransplantation for pancreas allograft thrombosis

Second and Third Chance to Stop Having Diabetes. Pancreas Retransplant With Functional Kidney Graft: A Single-Center Experience

BACKGROUND

Simultaneous pancreas-kidney (SPK) transplant is the primary option in patients with type 1 diabetes mellitus who develop end-stage kidney disease. Pancreas retransplant (PRt) has become an alternative in patients who experience pancreas graft failure (PGF). There is a lack of evidence regarding PRt in international registers. There are small series of published research with indeed heterogeneous results. We aim to compare PRt outcomes with primary SPK transplant in our center.

METHODS

The study was designed as a descriptive study of a cohort of 234 patients who received SPK transplant and received another PRt because of PGF at Reina Sofía University Hospital between 1988 and 2021. Kaplan-Meier analysis was performed to calculate patient and allograft survival.

RESULTS

Of these 234 SPK transplants, 53 pancreas grafts (22.6%) were lost initially. In total, 15 PRts were performed. The major cause of first PGF was surgical, whereas the medical cause was the most frequent in the PRt group. There were 60 deaths in the SPK group compared with only 1 in the PRt group. In Kaplan-Meier analysis, the PRt group showed worse survival than the SPK group, with statistically significant difference between groups (P = .05). Patient survival was not different between both groups.

CONCLUSIONS

PRt constitutes a viable option for recipients who experience PGF in the absence of formal contraindication. Although graft retransplant survival seems to be inferior to first graft in our series, these results are difficult to compare because of the scarce number of procedures performed.

Distal allograft pancreatectomy for graft salvage after pancreas transplantation

Early pancreas allograft failure most commonly results from vascular thrombosis. Immediate surgical intervention may permit pancreas allograft salvage, typically requiring thrombectomy. In cases of partial allograft necrosis secondary to splenic arterial thrombosis, distal allograft pancreatectomy may allow salvage of at least half of the pancreas allograft with retention of function. We retrospectively reviewed four cases of simultaneous pancreas and kidney recipients who required distal allograft pancreatectomy for splenic artery thrombosis with necrosis of the distal pancreas. Three of the four maintained long-term allograft function with euglycemia independent of insulin at six months to six years of follow-up, and all patients continue to maintain normal renal allograft function. Early diagnosis and early intervention are essential in order to salvage the pancreas allograft in the case of thrombosis. Distal allograft pancreatectomy can be performed safely and result in excellent long-term outcomes in select patients.

Late complications of pancreas transplant

To summarize the long-term complications after pancreas transplantation that affect graft function, a literature search was carried out on the long-term complications of pancreatic transplantation, namely, complications from postoperative 3^rd mo onwards, in terms of loss of graft function, late infection and vascular complications as pseudoaneurysms. The most relevant reviews and studies were selected to obtain the current evidence on these topics. The definition of graft failure varies among different studies, so it is difficult to evaluate, a standardized definition is of utmost importance to know the magnitude of the problem in all worldwide series. Chronic rejection is the main cause of long-term graft failure, occurring in 10% of patients. From the 3rd mo of transplantation onwards, the main risk factor for late infections is immunosuppression, and patients have opportunistic infections like: Cytomegalovirus, hepatitis B and C viruses, Epstein-Barr virus and varicella-zoster virus; opportunistic bacteria, reactivation of latent infections as tuberculosis or fungal infections. Complete preoperative studies and serological tests should be made in all recipients to avoid these infections, adding perioperative prophylactic treatments when indicated. Pseudoaneurysm are uncommon, but one of the main causes of late bleeding, which can be fatal. The treatment should be performed with radiological endovascular approaches or open surgery in case of failure. Despite all therapeutic options for the complications mentioned above, transplantectomy is a necessary option in approximately 50% of relaparotomies, especially in life-threatening complications. Late complications in pancreatic transplantation threatens long-term graft function. An exhaustive follow-up as well as a correct immunosuppression protocol are necessary for prevention.

Early technical pancreas failure in Simultaneous Pancreas-Kidney Recipients does not impact renal allograft outcomes

Early pancreas loss in simultaneous pancreas-kidney (SPK) transplants has been associated with longer perioperative recovery and reduced kidney allograft function. We assessed the impact of early pancreas allograft failure on transplant outcomes in a contemporary cohort of SPK patients (n = 218). Early pancreas allograft loss occurred in 12.8% (n = 28) of recipients. Delayed graft function (DGF) was more common (21.4% vs. 7.4%, p = 0.03) in the early pancreas loss group, but there were no differences in hospital length of stay (median 6.5 vs. 7.0, p = 0.22), surgical wound complications (p = 0.12), or rejection episodes occurring in the first year (p = 0.87). Despite differences in DGF, both groups had excellent renal function at 1 year post-transplant (eGFR 64.1 ± 20.8 vs. 65.8 ± 22.9, p = 0.75). There were no differences in patient (HR 0.58, 95% CI 0.18-1.87, p = 0.26) or kidney allograft survival (HR 0.84, 95% CI 0.23-3.06, p = 0.77). One- and 2-year protocol kidney biopsies were comparable between the groups and showed minimal chronic changes; the early pancreas loss group showed more cv changes at 2 years (p = 0.04). Current data demonstrate good outcomes and excellent kidney allograft function following early pancreas loss.

Outcomes after pancreas retransplantation: is the juice worth the squeeze?

PURPOSE OF REVIEW

Pancreas retransplantations are rarely carried out, and their outcomes are still debatable because of a lack of studies and clinical series on this issue.

RECENT FINDINGS

In general, pancreas retransplantations achieve similar or even higher patient survival than primary transplantations; however, it should be noted that this finding may be biased, as only healthier patients are selected for retransplantation. Graft survival in retransplantations is usually lower than that in primary transplantation, but this comparison may also be biased, as most retransplantations are solitary pancreas transplantations (which are known to have lower graft survival), whereas primary transplantations are mostly simultaneous kidney-pancreas transplantations. Technical loss is similar between primary pancreas transplantations and pancreas retransplantations, but the occurrence of surgical complications is greater in the latter.

SUMMARY

This review summarizes the literature on pancreas retransplantations, comparing them with primary transplantations, and demonstrates that in selected patients in experienced centres, retransplantation can be a valid and effective option for returning the patient to an insulin-free state.

Techniques of pancreas graft salvage/indications for allograft pancreatectomy

PURPOSE OF REVIEW

Despite improvements in pancreas allograft outcome, graft complications remain a significant cause of morbidity and mortality. This review analyses the issues involved in the management of conditions that may require graft pancreatectomy, including the indications and techniques for graft salvage.

RECENT FINDINGS

With early recognition of graft complications, liberal use of radiological interventions, improved infection control, access to critical care and innovative surgical techniques, graft salvage is now feasible in many circumstances where graft pancreatectomy would previously have been necessary.

SUMMARY

The outcome of pancreas transplantation continues to improve with advances in the management of graft-threatening complications.

Incidence and Indications for Late Allograft Pancreatectomy While on Continued Immunosuppression

BACKGROUND

There are limited data about the incidence and indications for late allograft pancreatectomy while on continued immunosuppression for functional kidney allografts.

METHODS

We analyzed recipients of simultaneous pancreas and kidney and pancreas after kidney transplants between January 1994 and July 2013. Patients with functional kidney but failed pancreas allografts after 90 days were included.

RESULTS

Out of 1022 simultaneous pancreas and kidney or pancreas after kidney recipients, 246 satisfied these criteria. Of these, 50 underwent allograft pancreatectomy (Px) and 196 did not (no-Px). Eleven of these pancreatectomies were performed at the time of repeat transplant and were analyzed separately. None of the basic recipient or donor characteristics differed significantly between the Px (n = 39) and no-Px groups, except for a higher proportion of females in the Px group. The most common presentation in the Px group was abdominal pain. Histopathology of the pancreas varied widely with graft thrombosis as the most common finding. In univariate and multivariate Cox regression analyses, only female recipient was associated with higher risk for allograft pancreatectomy. Px was not associated with kidney allograft survival (P = 0.16).

CONCLUSIONS

Despite the ongoing presence of full immunosuppression for a functioning kidney allograft, the need for Px for symptoms and radiological findings is not rare (39/246, 15.8%).

Simultaneous Kidney-Pancreas Transplantation With an Original "Transverse Pancreas" Technique: Initial 9 Years' Experience With 56 Cases

An innovative technique for pancreas transplantation is described. The main aspect consists of the horizontal positioning of the pancreas, which allows a better venous outflow, thus preventing thrombosis and graft loss. The program of pancreas transplantation in this national reference center for pancreatic and liver surgery was started in 2007; the initial results were considered poor, resulting in the loss of half of the grafts due to venous thrombosis. After analyzing the possible causes, this technique was proposed and successfully implemented, reducing the postoperative complications, particularly the problem of venous thrombosis. A detailed description of the new surgical technique is provided. The main clinical and demographic characteristics of the 56 patients who underwent the surgery are analyzed. The incidence of venous thrombosis was 5.3% (3 patients) and graft loss was 3.5% (2 patients). Due to the good results, this technique became the standard surgery for transplantation of the pancreas in our center. The technique proved to be safe and successful. Due to the unique pancreas graft implantation, we called it "transverse pancreas surgery."

Clinical Experience with Pancreas Graft Rescue From Severe Thrombus After Simultaneous Pancreas-Kidney Transplantation by Early Detection with Doppler Ultrasound: A Case Report

Patient: Female, 41

Final Diagnosis: Graft thrombosis

Symptoms: None

Medication: —

Clinical Procedure: Doppler ultrasound

Specialty: Transplantology

US Findings in Patients at Risk for Pancreas Transplant Failure

Purpose To determine if ultrasonographic (US) findings, including Doppler US findings, are associated with subsequent pancreas transplant failure. Materials and Methods A cohort of adult patients who underwent pancreas transplantation at a tertiary institution over the course of 10 years (from 2003 to 2012) was retrospectively evaluated for failure, which was defined as return to insulin therapy or surgical graft removal. The institutional review board provided a waiver of informed consent. All US images obtained within the 1st postoperative year were reviewed for three findings: arterial flow (presence or absence of intraparenchymal forward diastole flow), splenic vein thrombus, and edema. These findings were correlated with pancreas graft failure within 1-year after surgery by using Cox proportional hazards models and hazard ratios. Results A total of 228 transplants were included (mean patient age, 41.6 years; range, 19-57 years; 122 men, 106 women). Absent or reversed arterial diastolic flow was identified in nine of 20 failed transplants (sensitivity, 45%; 95% confidence interval [CI]: 23, 68) and in 15 of 208 transplants that survived (specificity, 93% [193 of 208]; 95% CI: 89, 96). The Cox proportional hazard ratio was 6.2 (95% CI: 3.1, 12.4). Splenic vein thrombus was identified in 10 of 20 failed transplants (sensitivity, 50%; 95% CI: 27, 73) and in 25 of 208 transplants that survived (specificity, 88% [183 of 208]; 95% CI: 83, 92). The Cox proportional hazard ratio was 4.2 (95% CI: 2.4, 7.4). Edema had the lowest specificity (Cox proportional hazard ratio, 2.0; 95% CI: 1.3, 2.9). In the multivariate analysis, only absent or reversed arterial diastolic flow remained significantly associated with transplant failure (adjusted hazard ratio, 3.6; 95% CI: 1.0, 12.8; P = .045). Conclusion Absent or reversed diastolic arterial Doppler flow has a stronger association with transplant failure than does splenic vein thrombus or edema. (©) RSNA, 2016.

Allograft Pancreatectomy: Indications and Outcomes

This study evaluated the indications, surgical techniques, and outcomes of allograft pancreatectomy based on a single center experience. Between 2003 and 2013, 47 patients developed pancreas allograft failure, excluding mortality with a functioning pancreas allograft. Early graft loss (within 14 days) occurred in 16, and late graft loss in 31. All patients with early graft loss eventually required allograft pancreatectomy. Nineteen of 31 patients (61%) with late graft loss underwent allograft pancreatectomy. The main indication for early allograft pancreatectomy included vascular thrombosis with or without severe pancreatitis, whereas one recipient required urgent allograft pancreatectomy for gastrointestinal hemorrhage secondary to an arterioenteric fistula. In cases of late allograft pancreatectomy, graft failure with clinical symptoms such as abdominal discomfort, pain, and nausea were the main indications (13/19 [68%]), simultaneous retransplantation without clinical symptoms in 3 (16%), and vascular catastrophes including pseudoaneurysm and enteric arterial fistula in 3 (16%). Postoperative morbidity included one case each of pulmonary embolism leading to mortality, formation of pseudoaneurysm requiring placement of covered stent, and postoperative bleeding requiring relaparotomy eventually leading to femoro-femoral bypass surgery 2 years after allograftectomy. Allograft pancreatectomy can be performed safely, does not preclude subsequent retransplantation, and may be lifesaving in certain instances.

Pancreatic retransplantation is associated with poor allograft survival: an update of the United Network for Organ Sharing database

The aim of the study was to assess outcomes of pancreas retransplantation versus primary pancreas transplantation.

METHODS

Data from the United Network for Organ Sharing database on all adult (age, ≥18 years) subjects who received pancreas and kidney-pancreas transplants between 1996 and 2012 were analyzed (n = 20,854). The subjects were analyzed in the following 2 groups: retransplant (n = 1149) and primary transplant (n = 19,705).

RESULTS

Kaplan-Meier analysis demonstrated significantly different patient survival (P < 0.0001) and death-censored graft survival (P < 0.0001) between the primary transplant versus retransplant subjects. Allograft survival was significantly poorer in the retransplantation group. Patient survival was greater in the retransplant group.

CONCLUSIONS

The results of our study differ from previous studies, which showed similar allograft survival in primary and secondary pancreas transplants. Further studies may elucidate specific patients who will benefit from retransplantation. At the present time, it would appear that pancreas retransplantation is associated with poor graft survival and that retransplantation should not be considered for all patients with primary pancreatic allograft failure.

Outcomes of pancreas retransplantation after simultaneous kidney-pancreas transplantation are comparable to pancreas after kidney transplantation alone

BACKGROUND

There is a paucity of contemporary data describing the results of pancreas retransplantation (PRT). As a measure of utility, we wished to determine whether PRT could produce equivalent short-term and long-term recipient outcomes to primary pancreas after kidney (PAK) transplantation.

METHODS

Retrospective analysis of 96 consecutive pancreas only transplants performed from 2003 to May 2012. Primary PAK transplants (n = 78) were compared to PRT (n=18).

RESULTS

Donor and recipient demographics were similar. Pancreas graft survival was similar for PAK and PRT at 1 year (88.2% vs. 100%) and 3 years (85.1% vs. 85.1%). Pancreas graft failure occurred in 14 PAK and two PRT patients with a mean follow-up of 61.6 ± 38.7 and 37.8 ± 26.1 months, respectively. There were no differences in postoperative length of stay (9.9 days vs. 8.7 days; P = 0.9) or postoperative complications in the first 3 months (47.4% vs. 38.9%, P = 0.6). At 3-year follow-up, both groups had comparable HBA1c (0.06 vs. 0.05; P = 0.8), serum creatinine (116.6 μmol/L v 131.7 μmol/L; P = 0.09), and oral glucose tolerance tests.

CONCLUSION

Pancreas retransplantation is a safe and effective therapy for select recipients after graft loss. Pancreas retransplantation is associated with the same risk of postoperative complications and has similar intermediate-term graft survival compared to primary PAK transplantation.

Functioning pancreas graft with thromboses of splenic and superior mesenteric arteries after simultaneous pancreas-kidney transplantation: a case report

Graft thrombosis is the most common cause of early graft loss after pancreas transplantation. The grafted pancreas is difficult to salvage after complete thrombosis, especially arterial thrombosis, and graft pancreatectomy is required. We describe a patient presenting with a functioning pancreas graft with thromboses of the splenic artery (SA) and superior mesenteric artery (SMA) after simultaneous pancreas-kidney transplantation (SPK). A 37-year-old woman with a 20-year history of type 1 diabetes mellitus underwent SPK. The pancreaticoduodenal graft was implanted in the right iliac fossa with enteric drainage. A Carrel patch was anastomosed to the recipient's right common iliac artery, and the graft gastroduodenal artery was anastomosed to the common hepatic artery using an arterial I-graft. The donor portal vein was anastomosed to the recipient's inferior vena cava. Four days after surgery, graft thromboses were detected by Doppler ultrasound without increases in the serum amylase and blood glucose levels. Contrast enhanced computed tomography revealed thromboses in the SA, splenic vein and SMA. Selective angiography showed that blood flow was interrupted in the SA and SMA. However, pancreatic graft perfusion was maintained by the I-graft in the head of the pancreas and the transverse pancreatic artery in the body and tail of the pancreas. We performed percutaneous direct thrombolysis and adjuvant thrombolytic therapy. However, we had to stop the thrombolytic therapy because of gastrointestinal hemorrhage. Thereafter, the postoperative course was uneventful and the pancreas graft was functioning with a fasting blood glucose level of 75 mg/dL, HbA1c of 5.1%, and serum C-peptide level of 1.9 ng/mL at 30 months post-transplantation.

Cooperative Study of the Spanish Pancreas Transplant Group (GETP): Surgical Complications

Technical failure in pancreas transplant has been the main cause of the loss of grafts. In the last few years, the number of complications has reduced, and therefore the proportion of this problem.

OBJECTIVES

The Spanish Pancreas Transplant Group wanted to analyze the current situation with regard to surgical complications and their severity.

MATERIAL AND METHODS

A retrospective and multicenter study was performed. 10 centers participated, with a total of 410 pancreas transplant recipients between January and December 2013.

RESULTS

A total of 316 transplants were simultaneous with kidney, 66 after kidney, pancreas-only 10, 7 multivisceral and 11 retrasplants. Surgical complication rates were 39% (n=161). A total of 7% vascular thrombosis, 13% bleeding, 6% the graft pancreatitis, 12% surgical infections and others to a lesser extent. Relaparotomy rate was 25%. The severity of complications were of type IIIb (13%), type II (12%) and type IVa (8.5%). Graft loss was 8%. Early mortality was 0.5%. The percentage of operations for late complications was 17%.

CONCLUSIONS

The number of surgical complications after transplantation is not negligible, affecting one in 3 patients. They are severe in one out of 5 and, in one of every 10 patients graft loss occurs. Therefore, there is still a significant percentage of surgical complications in this type of activity, as shown in our country.

Clinical outcomes associated with the early postoperative use of heparin in pancreas transplantation

BACKGROUND

Graft thrombosis following pancreas transplantation is the leading non-immunologic cause of graft loss. Routine systemic anticoagulation is controversial because of an increased bleeding risk.

METHODS

This was a retrospective, single-center analysis including all pancreas transplants performed over 9 years evaluating the use of low-dose heparin in the early postoperative period. Clinical outcomes were partial and complete graft thrombosis within 30 days, bleeding events, relaparotomy rates, and 30-day graft and patient survival. Multivariate regression analysis was performed to identify risk factors for early graft loss resulting from thrombosis.

RESULTS

One hundred fifty-two patients were included, 52 in the heparin group. The overall complete thrombosis rate was 13.1%, 10% in those who received heparin, and 15% in those who did not. Partial thrombosis was higher in the heparin group (10% vs. 3%). Higher relaparotomy rates were seen in the heparin group (29% vs. 22%); however, bleeding events were similar between groups. Graft and patient survival at 30 days were similar between groups; however, there was a trend toward higher graft survival in the heparin group. Heparin showed a trend toward a protective benefit for early graft loss resulting from thrombosis in all multivariate regression models.

CONCLUSION

These data suggest low-dose heparin early in the postoperative period may provide a protective benefit in the prevention of early graft loss resulting from thrombosis, without an increased risk of bleeding.

Reversal of diabetes in mice with a bioengineered islet implant incorporating a type I collagen hydrogel and sustained release of vascular endothelial growth factor

We have developed a bioengineered implant (BI) to evaluate strategies to promote graft survival and function in models of islet transplantation in mice. The BI, sized for implantation within a fold of intestinal mesentery, consists of a disk-shaped, polyvinyl alcohol sponge infused with a type I collagen hydrogel that contains dispersed donor islets. To promote islet vascularization, the BI incorporates a spherical alginate hydrogel for sustained release of vascular endothelial growth factor (VEGF). BIs that contained 450-500 islets from syngeneic (C57Bl/6) donors and 20 ng of VEGF reversed streptozotocin (STZ)-induced diabetes in 100% of mice (8/8), whereas BIs that contained an equivalent number of islets, but which lacked VEGF, reversed STZ-induced diabetes in only 62.5% of mice (5/8). Between these "+VEGF" and "-VEGF" groups, the time to achieve normoglycemia (8-18 days after implantation) did not differ statistically; however, transitory, postoperative hypoglycemia was markedly reduced in the +VEGF group relative to the -VEGF group. Notably, none of the mice that achieved normoglycemia in these two groups required exogenous insulin therapy once the BIs began to fully regulate levels of blood glucose. Moreover, the transplanted mice responded to glucose challenge in a near-normal manner, as compared to the responses of healthy, nondiabetic (control) mice that had not received STZ. In future studies, the BIs described here will serve as platforms to evaluate the capability of immunomodulatory compounds, delivered locally within the BI, to prevent or reverse diabetes in the setting of autoimmune (type 1) diabetes.

Pancreas graft thrombosis: causes, prevention, diagnosis, and intervention

PURPOSE OF REVIEW

Pancreas graft thrombosis remains one of the most common reasons for pancreas transplant loss. Patients with a history of thrombotic events should be identified and evaluated for thrombophilia to identify transplant candidates at highest risk.

RECENT FINDINGS

Early after transplant, vascular thrombosis is multifactorial, but beyond 2 weeks, inflammation or acute rejection predominate as the cause of thrombosis. Most pancreas transplant centers utilize some form of anticoagulation following transplantation. Aspirin is highly recommended. Unfractionated or low-molecular-weight heparin is often administered, but some centers use heparin selectively and typically at low dose to avoid postoperative bleeding. Warfarin is less frequently given and its use should probably be limited to patients with thrombophilia.

SUMMARY

Thrombectomy, either surgical or percutaneous, may salvage the pancreas graft if performed early after the occurrence of thrombosis.

Pancreas transplantation: a single-institution experience in Japan

Purpose

We herein report our experience with pancreas transplantation in 26 patients at a single institution in Japan between August 2001 and December 2011.

Methods

We reviewed the medical records of 26 pancreas transplantations performed in our institute.

Results

The early complications (within 2 weeks) included one graft venous thrombosis, one arterial thrombosis, and two reoperations for bleeding. Of the 26 pancreas transplant recipients, five lost pancreas graft function. Of 24 simultaneous pancreas–kidney recipients, three lost kidney graft function due to noncompliance. The patient, pancreas, and kidney survival rates were 100, 96 and 93 % at 1 year; 100, 80 and 93 % at 5 years; and 100, 67 and 68 % at 10 years, respectively. Of all these complications, venous thrombosis after pancreas transplantation was the most critical.

Conclusions

As the largest series of pancreas transplantations in a single institution in Japan, our series yielded better results than the worldwide data recorded by the International Pancreas Transplant Registry. Routine postoperative anticoagulation therapy is not necessary for the prevention of graft thrombosis if sufficient fluid infusion is strictly controlled and the graft blood flow is frequently monitored. When graft thrombosis occurs, both early detection and appropriate intervention are extremely important if the pancreas graft is to survive.

Prevention and management of graft thrombosis in pancreatic transplant

Pancreatic transplant effectively cures type 1 diabetes mellitus and maintains consistent long-term euglycemia. However, technical failure, and in particular graft thrombosis, accounts for the vast majority of transplants lost in the early postoperative period. The pancreas' inherently low microvascular flow state makes it vulnerable to vascular complications, as does the hypercoagulable blood of diabetic patients. Ultimately, the phenomenon is most definitely multifactorial. Prevention, as opposed to treatment, is key and should focus on reducing these multiple risk factors. This will involve tactical donor selection, optimal surgical technique and some form of anticoagulation. Close monitoring and early intervention will be crucial when treating thrombosis once preventative methods have failed. This may be achieved by further anticoagulation, graft salvage, or pancreatectomy with retransplant. This article will explore the multiple factors contributing to graft thrombus formation and the ways in which they may be addressed to firstly prevent, or more likely, reduce thrombosis. Secondly, we will consider the management strategies which can be implemented once thrombosis has occurred.

Early reexploration for suspected thrombosis after pancreas transplantation

BACKGROUND

Graft thrombosis is the most common cause of early graft loss after pancreas transplantation. Early reexploration may permit salvage or timely removal of the thrombosed graft.

METHODS

This was a retrospective review of 345 pancreas transplants performed at a single center between January 2003 and December 2009. Early reexploration was defined as within 1 week of pancreas transplantation.

RESULTS

Of the 345 transplants, there were 35 early reexplorations. The graft was compromised in 20 cases (57%): 10 venous thromboses, 3 arterial thromboses, 2 combined arterial and venous thrombosis, 2 thromboses secondary to allograft pancreatitis, and 3 cases of positional ischemia without thrombosis. Of these allografts, three reperfused once repositioned and six were successfully thrombectomized for a graft salvage rate of 45%. One of the thrombectomized grafts remained perfused but never functioned and was removed at retransplantation. The 10 remaining compromised grafts that were deemed unsalvageable and required allograft pancreatectomy. Nine of these recipients were retransplanted (eight within 2 weeks) and one was not a retransplantation candidate.

CONCLUSIONS

Reexploration for suspected graft thrombosis after pancreas transplantation resulted in a negative laparotomy rate of 43%, but permitted graft salvage in 45% of compromised grafts.

Pancreatic graft survival despite partial vascular graft thrombosis due to splenocephalic anastomoses

Thrombotic complications following pancreas transplantation are still the most common cause of nonimmunologic graft loss. The aim of this study was to analyze pancreatic graft function after partial arterial graft thrombosis and the investigation of the pancreatic arterial anatomy with regard to intraparenchymal anastomoses. We retrospectively analyzed the data for 175 consecutive pancreas transplants performed between January 2002 and October 2007. Selective Y-graft angiography was performed in 10 and rubber-milk injection in 5 fresh pancreas specimens. Thrombosis of one leg of the Y-graft was diagnosed in 18 (10.3%) patients. Only one of these patients with thrombosis of the splenic artery required exogenous insulin. Sufficient graft perfusion was demonstrated in all of the remaining grafts. One graft was lost due to acute rejection. In all specimens angiography showed an excellent perfusion of the pancreaticoduodenal arcade, even after selective cannulation of the splenic artery. Arterial collaterals between the gastroduodenal, splenic artery and the superior mesenteric artery were demonstrated. Our results demonstrate that global perfusion of the pancreatic graft and sufficient graft function is sustained after the thrombotic occlusion of one branch of the Y-graft by a complex system of intraparenchymal anastomoses. These anatomical findings may have consequences for resection strategies in pancreas surgery.

Complications after pancreas transplantation

PURPOSE OF REVIEW

The history of transplantation of the pancreas, unlike that of transplantation of other abdominal organs, has largely been shaped by the associated surgical complications. After more than three decades of progress, surgical-technical pancreas graft failure rates have decreased to approximately 8%. The most recent developments in this area are systematically reviewed in this article.

RECENT FINDINGS

Vascular graft thrombosis remains, by far, the most common cause of technical graft failure. Recent reports suggested that pancreas preservation with histidine-tryptophan-ketoglutarate solution (HTK) might be a risk factor for reperfusion pancreatitis, graft thrombosis and decreased short- and long-term graft survival. It remains unclear whether these results are, at least in part, related to HTK flush volumes and extended preservation (e.g.,>12 h). For selected thrombosed pancreas grafts, there has been renewed interest in pharmacological, interventional, and surgical salvage. For selected recipients with early pancreas graft thrombosis not amenable to a salvage intervention, transplant pancreatectomy in conjunction with immediate retransplantation has emerged as a viable option. For graft thrombosis prevention, the enhanced backtable pancreas vascular reconstruction techniques (e.g., gastroduodenal artery revascularization) proposed by some authors await more formal study. For prevention of native vascular complications in high-risk recipients, several technical modifications have been reported. Developments with respect to other surgical complications (wound infection, pancreatitis, leak, and bleeding) have been more incremental.

CONCLUSION

Recent evidence underscores the importance of judicious donor and recipient selection and of optimization of preservation and surgical factors for excellent short- and long-term pancreas transplant outcomes.