Growth of a nation part II: impact of recipient obesity on whole-organ pancreas transplantation

Single-center retrospective assessment of robotic-assisted simultaneous pancreas-kidney transplants: Exploring clinical utility

The diabetic population is witnessing a rise in obesity rates, creating specific hurdles for individuals seeking pancreas transplantation because they are frequently disqualified due to their elevated body weight. Introducing a robotic-assisted approach to transplantation has been proven to yield improved outcomes, particularly in patients with obesity. A retrospective analysis was conducted between January 2015 and September 2023. The study included a total of 140 patients, with 16 receiving robotic-assisted simultaneous pancreas-kidney transplantation (RSPK) and 124 undergoing open approach simultaneous pancreas-kidney transplantation (OSPK) during the study period. The median age was 45 (36.8-52.7) and 44.5 years (36.8-51.8) (RSPK vs OSPK, P = .487). There were no significant differences in demographics except body mass index (RSPK vs OSPK, 34.9 vs 28.1, P < .001) and a higher percentage of patients with high cardiac risk in the RSPK group. The robotic approach has a lengthier overall operative time and warm ischemia time. Surgical and nonsurgical complications at 30-days and 1-year grafts and patient survival (93.8% vs 96.8%, RSPK vs OSPK, P = .521) were similar. Our findings suggest that employing robotic assistance in simultaneous pancreas-kidney transplantation is safe. Wider adoption and utilization of this technique could potentially improve transplant accessibility for individuals with obesity and diabetes.

Modern indications for referral for kidney and pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation (PTx) is currently the only therapy that can predictably achieve sustained euglycemia independent of exogenous insulin administration in patients with insulin-dependent diabetes mellitus. This procedure involves a complex abdominal operation and lifetime dependence on immunosuppressive medications. Therefore, PTx is most frequently performed in combination with other organs, usually a kidney transplant for end stage diabetic nephropathy. Less frequently, solitary PTx may be indicated in patients with potentially life-threatening complications of diabetes mellitus. There remains confusion and misperceptions regarding indications and timing of patient referral for PTx.

RECENT FINDINGS

In this review, the referral, evaluation, and listing process for PTx is described, including a detailed discussion of candidate assessment, indications, contraindications, and outcomes.

SUMMARY

Because the progression of diabetic kidney disease may be less predictable than other forms of kidney failure, early referral for planning of renal and/or pancreas transplantation is paramount to optimize patient care and allow for possible preemptive transplantation.

Pancreas Transplantation in Minorities including Patients with a Type 2 Diabetes Phenotype

Background: Prior to year 2000, the majority of pancreas transplants (PTx) were performed as simultaneous pancreas-kidney transplants (SPKTs) in Caucasian adults with end stage renal failure secondary to type 1 diabetes mellitus (T1DM) who were middle-aged. In the new millennium, improving outcomes have led to expanded recipient selection that includes patients with a type 2 diabetes mellitus (T2DM) phenotype, which excessively affects minority populations. Methods: Using PubMed® to identify appropriate citations, we performed a literature review of PTx in minorities and in patients with a T2DM phenotype. Results: Mid-term outcomes with SPKT in patients with uremia and circulating C-peptide levels (T2DMphenotype) are comparable to those patients with T1DM although there may exist a selection bias in the former group. Excellent outcomes with SPKT suggests that the pathophysiology of T2DM is heterogeneous with elements consisting of both insulin deficiency and resistance related to beta-cell failure. As a result, increasing endogenous insulin (Cp) production following PTx may lead to freedom checking blood sugars or taking insulin, better metabolic counter-regulation, and improvements in quality of life and life expectancy compared to other available treatment options. Experience with solitary PTx for T2DM or in minorities is limited but largely mirrors the trends reported in SPKT. Conclusions: PTx is a viable treatment option in patients with pancreas endocrine failure who are selected appropriately regardless of diabetes type or recipient race. This review will summarize data that unconventional patient populations with insulin-requiring diabetes may gain value from PTx with an emphasis on contemporary experiences and appropriate selection in minorities in the new millennium.

Simultaneous Pancreas-Kidney Transplantation Versus Living Donor Kidney Transplantation Alone: an Outcome-Driven Choice?

PURPOSE OF REVIEW

The choice of optimum transplant in a patient with type 1 diabetes mellitus (T1DM) and chronic kidney disease stage V (CKD V) is not clear. The purpose of this review was to investigate this in more detail-in particular the choice between a simultaneous pancreas-kidney transplantation (SPKT) and living donor kidney transplantation (LDKT), including recent evidence, to aid clinicians and their patients in making an informed choice in their care.

RECENT FINDINGS

Analyses of large databases have recently shown SPKT to have better survival rates than a LDKT in the long-term, despite an early increase in morbidity and mortality in SPKT recipients. This survival advantage has only been shown in those SPKT recipients with a functioning pancreas and not those who had early pancreas graft loss. The choice of SPKT or LDKT should not be based on patient and graft survival outcomes alone. Individual patient circumstances, preferences, and comorbidities, among other factors should form an important part of the decision-making process. In general, an SPKT should be considered in those patients not on dialysis and LDKT in those nearing or already on dialysis.

Robotic Pancreas Transplantation

Obesity is considered a relative contraindication to pancreas transplantation due to an overall increased risk in wound-related complications and surgical site infections. The rationale for performing pancreas transplantation in a minimally invasive fashion is to reduce these risks, which can be associated with inferior patient and graft survival following pancreas transplantation in morbidly obese patients. At the University of Illinois at Chicago, the initial series of robotic-assisted pancreas transplantation in obese patient with type 1 and 2 diabetes has been performed. In this article, surgical technique and world experience in robotic pancreas transplantation are described.

Pancreas transplantation in unconventional recipients

PURPOSE OF REVIEW

Advances in surgical technique and immunosuppression have significantly improved outcomes after pancreas transplantation, and as a result pancreas transplants increasingly are being performed for indications other than type 1 diabetes mellitus. This review summarizes the current literature on pancreas transplantation in unconventional recipient populations.

RECENT FINDINGS

An increasing body of work suggests that pancreas transplantation can be performed with good outcomes in patients with type 2 diabetes mellitus and those 50 years of age and older. Obesity appears detrimental to patient and pancreas graft survival, and bariatric surgery prior to transplantation may be of increasing interest and relevance. There are limited data yielding mixed outcomes on pancreas transplantation in patients with HIV or hepatitis C virus. However, rapidly improving antiviral therapies are prolonging survival in patients with HIV and chronic hepatitis C virus infections and may increase the number of candidates available for pancreas transplantation in these populations in the future.

SUMMARY

Despite limited literature in these patient populations, pancreas transplantation may be a viable treatment option for endocrine pancreas failure in appropriately selected patients regardless of disease cause or age.

Significance of steatosis in pancreatic transplantation

The on-going success of whole organ pancreatic transplantation is dependent on overcoming the imbalance between demand and supply of optimal organs as well as tackling the vast comorbidity associated with the procedure. Pancreas steatosis is a common contributing factor to the problem and with obesity pandemics affecting the global population; the size and type of organs received from donors will only make steatosis more of an issue. The aim of this review is to highlight what is known about steatosis in the context of pancreas transplantation identifying potential methods to help its evaluation. Narrative review of literature from inception to June 2017, using OVID interface searching EMBASE and MEDLINE databases as well recent transplant conference data. All studies related to pancreas steatosis examined for clinical relevance with no exclusion criteria. Key ideas extracted and referenced. Pancreatic steatosis is not innocuous and is precariously regarded by transplant surgeons, however its associations with obesity, metabolic syndrome and long list of associated complications clearly show it needs more careful consideration. Radiologic and surgical advances now allow assessment of the fat content of organs, which could be used to quantify organs allowing better optimisation, but there is still much work to be done to refine the optimal method to achieve this.

Robotic pancreas transplantation in a type 1 diabetic patient with morbid obesity: A case report

RATIONALE

Obesity is considered a relative contraindication to pancreas transplantation due to increased risks of wound-related complications. Robotic surgeries have never been applied for pancreas transplantation in obese recipients though robotic kidney transplantation did and already proved its value in reducing wound-related complications in obese recipients.

PATIENT CONCERNS & DIAGNOSES

We performed the first robotic pancreas after kidney transplantation for a 34-year-old Hispanic type 1 diabetic male with class III obesity (BMI = 41 kg/m).

INTERVENTIONS

The pancreas graft was procured and benched in the standard fashion. Methylene blue was used to detect any vascular leaks. The operation was completed via two 12-mm ports (camera, laparoscopic bed-side assistance), two 8-mm ports for robotic arms, and a 7-cm epigastric incision for hand port. The portal vein and arterial Y-graft of the pancreas were anastomosed to the recipient's left external iliac vein and artery, respectively. Duodenum-bladder drainage was performed with a circular stapler.

OUTCOMES

Duration of warm and cold ischemia was: 45 minutes and 7 hours, respectively. The patient was discharged uneventfully without wound-related complications. Excellent metabolic control was achieved with hemoglobin A1c lowering from 9% before transplantation to 4.4% on day 120. The patient remained in nondiabetic status in 1-year follow-up.

LESSONS

In conclusion, robotic pancreas transplantation is feasible in patients with morbid obesity.

Impact of recipient body mass index on short-term and long-term survival of pancreatic grafts

BACKGROUND

The impact of recipient body mass index on graft and patient survival after pancreas transplantation is not well known.

METHODS

We have analyzed data from all pancreas transplant recipients reported in the Scientific Registry of Transplant Recipients between 1987 and 2011. Recipients were categorized into BMI classes, as defined by the World Health Organization. Short-term (90 days) and long-term (90 days to 5 years) patient and graft survivals were analyzed according to recipient BMI class using Kaplan-Meier estimates. Hazard ratios were estimated using Cox proportional hazard models.

RESULTS

A total of 21,075 adult recipients were included in the analysis. Mean follow-up was 5 ± 1.1 years. Subjects were overweight or obese in 39%. Increasing recipient BMI was an independent predictor of pancreatic graft loss and patient death in the short term (P<0.001), especially for obese class II patient survival (hazard ratio, 2.07; P=0.009). In the long term, obesity, but not overweight, was associated with higher risk of graft failure (P=0.01). Underweight was associated with a higher risk of long-term death (P<0.001).

CONCLUSION

These results question the safety of pancreas transplantation in obese patients and suggest that they may be directed to alternate therapies, such as behavioral modifications or bariatric surgery, before pancreas transplantation is considered.

Obesity and organ transplantation: successes, failures, and opportunities

The increasing rate of societal obesity is also affecting the transplant world through obesity in candidates and donors as well as its posttransplant repercussions. Being overweight and obese has been shown to have significant effects on both short- and long-term complications as well as patient and graft survival. However, much of the comorbidity can be controlled or prevented with careful patient selection and aggressive management. A team approach to managing obesity and its comorbidities both pre- and posttransplant is essential for successful transplant outcomes. Complicating understanding the results of obesity research is the inclusion different weight categories, use of listing vs transplant weights, patient populations large enough for statistical power, and changes in transplant management, especially immunosuppression protocols, anti-infection protocols, and operative techniques. Much more research is needed regarding many elements, including safe weight loss before transplantation, prevention of weight gain after transplant, genomic influences, and the role of bariatric surgery in the transplant process.

Kidney transplant options for the diabetic patient

For patients with diabetes and progressive chronic kidney disease, kidney transplantation is the optimal mode of renal replacement therapy, with or without a pancreas transplant. Additional benefits of pancreas transplant have become increasingly apparent due to advances in surgical outcomes and immunosuppression, and may be reasonably considered even in selected patients with type 2 diabetes. In general, pancreas transplantation is associated with long-term survival advantages despite an increased short-term morbidity and mortality risk. This is true with simultaneous pancreas kidney transplantation or pancreas after kidney transplantation compared to kidney transplantation alone, regardless of kidney donor status (living or deceased). Individual patient preferences, comorbidities, and expected waiting time influence selection of transplant modality, rather than a clear survival benefit of one strategy versus the other. In selected patients with type 2 diabetes, recent outcomes data support cautious utilization of simultaneous pancreas kidney transplantation when a living kidney donor transplant is not an option. The purpose of this review is to summarize current data regarding kidney and pancreas transplant treatment options in patients with both type 1 and 2 diabetes and the influence of current organ allocation policies to better understand the advantages and disadvantages of each of these strategies.

Early pancreas allograft thrombosis

OBJECTIVES

To determine factors associated with early pancreatic allograft thrombosis (EPAT). Thrombosis is the leading non-immunological cause of early pancreatic allograft failure. Multiple risk factors have been postulated. We hypothesized that recipient perioperative hypotension was a major risk factor and evaluated the correlation of this and other parameters with EPAT.

METHODS

We retrospectively reviewed the records of the 118 patients who received a pancreatic allograft at our center between October 1992 and January 2010. Multiple donor and recipient parameters were analyzed as associates of EPAT by univariate and multivariate analysis.

RESULTS

There were 12 episodes of EPAT, resulting in an incidence of 10.2%. On univariate analysis, EPAT was associated with perioperative hypotension, vasopressor use, and neuropathy in the recipient (p ≤ 0.04 for all). On multivariate analysis corrected for age, sex, and peripheral vascular disease, only vasopressor use retained a significant association with EPAT with a hazard ratio of 8.74 (CI 1.11-68.9, p = 0.04). Factors associated with vasopressor use included recipient ischemic heart disease, peripheral vascular disease, retinopathy or neuropathy, and any surgical complication.

CONCLUSIONS

Significant hypotension, measured by the need for perioperative vasopressor use was associated with EPAT, suggesting that maintenance of higher perfusion pressures may avoid this complication.

Recipient and donor body mass index as important risk factors for delayed kidney graft function

BACKGROUND

Obesity is increasingly impacting the overall health status and the global costs for health care. The increase in body mass index (BMI) is also observed in kidney allograft recipients and deceased organ donors.

METHODS

In a retrospective single-center study, we analyzed 1132 deceased donor kidney grafts, transplanted at our institution between 2000 and 2009 for recipient and donor BMI and its correlation with delayed graft function (DGF). Recipients/donors were classified according to their BMI (<18.5, 18.5-24.9, 25-29.9, and >30 kg/m(2)). DGF was defined as requirement for one dialysis within the first week after transplantation.

RESULTS

Overall DGF rate was 32.4%, mean recipient BMI was 23.64 ± 3.75 kg/m(2), and mean donor BMI was 24.69 ± 3.44 kg/m(2). DGF rate was 25.2%, 29.8%, 40.9%, and 52.6% in recipients with BMI less than 18.5, 18.5 to 24.9, 25 to 29.9, and more than 30 kg/m, respectively (P<0.0001). Donor BMI less than 18.5, 18.5 to 24.9, 25 to 29.9, more than 30 kg/m(2) resulted in a DGF rate of 22.5%, 31.0%, 37.3%, and 51.2% (P < 0.0001). Multivariate analysis revealed recipient BMI and dialysis duration as independent risk factors for DGF. DGF results in inferior 1- and 5-year graft and patient survival.

CONCLUSION

Recipient and donor BMI correlate with the incidence of DGF. Awareness thereof should have an impact on peri- and posttransplant measures in renal transplant recipients.

Pancreas transplantation after bariatric surgery

Obese transplant candidates are at increased risk for perioperative and postoperative complications. In many transplant programs, morbid obesity is considered to be an exclusion criterion for transplantation. The only potential option that would grant these patients access to transplant is weight loss. Non-operative weight loss strategies such as behavioral modifications, exercise, diet, or medication have only very limited success in achieving long-term weight loss. In contrast, bariatric surgery was shown to achieve not only more excessive weight loss, but more importantly, this weight loss can be sustained for longer periods of time. Therefore, bariatric surgery presents an attractive option for weight loss for morbidly obese transplant candidates. We report our experience with four patients who underwent bariatric surgery prior to successful pancreas transplantation. Even though gastric bypass and laparoscopic adjustable gastric band present as equivalent alternatives for weight reduction, we believe that in the population of morbidly obese diabetic patients who are possible candidates for pancreas transplantation, laparoscopic adjustable gastric band placement is the more suitable procedure.