Lung transplantation in primary pulmonary arterial hypertension and pulmonary venous hypertension.

OBJECTIVES: End-stage lung disease from primary pulmonary hypertension (PPHTN) and pulmonary venous-occlusive disease (PVOD) may require lung transplantation (LT). While medical therapies exist for the palliation of PPHTN, no therapies exist for PVOD. The study's objective is to compare outcomes of LT in these patients. METHODS: Patients with PPHTN and PVOD who had undergone LT were identified in the UNOS database (2005-2022). Univariable analyses compared differences between groups in demographic, clinical, and post-transplant outcomes. Multivariable logistic regression examined the association between the diagnosis group and survival. Overall survival time between groups was compared using the Kaplan-Meier method. RESULTS: Six hundred and ninety-six PPHTN and 78 PVOD patients underwent LT during the study period. Patients with PVOD had lower pulmonary artery mean pressure (47 vs. 53 mmHg, p < .001), but higher cardiac output (4.51 vs. 4.31 L/min, p = .04). PVOD patients were more likely to receive lungs from donation after cardiac death donors (7.7 vs. 2.9%, p = .04). There were no differences in postoperative complications or length of stay. PVOD was associated with superior survival at 30-day (100 vs. 93%, p = .02) and 90-day post-transplant (93 vs. 83%, p = .03), but not at later time points. In multivariable analyses, PVOD and brain death donor use were associated with better survival up to 90-day mark. CONCLUSIONS: Patients undergoing LT for PVOD had better initial survival, which disappeared after 1 year of transplantation. Donation after circulatory death donor use had a short-term survival disadvantage.

Abdominal normothermic regional perfusion in controlled donation after circulatory determination of death liver transplantation: Outcomes and risk factors for graft loss.

Postmortem normothermic regional perfusion (NRP) is a rising preservation strategy in controlled donation after circulatory determination of death (cDCD). Herein, we present results for cDCD liver transplants performed in Spain 2012-2019, with outcomes evaluated through December 31, 2020. Results were analyzed retrospectively and according to recovery technique (abdominal NRP [A-NRP] or standard rapid recovery [SRR]). During the study period, 545 cDCD liver transplants were performed with A-NRP and 258 with SRR. Median donor age was 59 years (interquartile range 49-67 years). Adjusted risk estimates were improved with A-NRP for overall biliary complications (OR 0.300, 95% CI 0.197-0.459, p < .001), ischemic type biliary lesions (OR 0.112, 95% CI 0.042-0.299, p < .001), graft loss (HR 0.371, 95% CI 0.267-0.516, p < .001), and patient death (HR 0.540, 95% CI 0.373-0.781, p = .001). Cold ischemia time (HR 1.004, 95% CI 1.001-1.007, p = .021) and re-transplantation indication (HR 9.552, 95% CI 3.519-25.930, p < .001) were significant independent predictors for graft loss among cDCD livers with A-NRP. While use of A-NRP helps overcome traditional limitations in cDCD liver transplantation, opportunity for improvement remains for cases with prolonged cold ischemia and/or technically complex recipients, indicating a potential role for complimentary ex situ perfusion preservation techniques.

Pediatric living donor intestine transplant following an atypical complication of COVID-19: A unique case report from India.

Coronavirus disease-19 (COVID-19) infection causing severe gastrointestinal complications is rare. A 9-year-old child after recovering from mild COVID-19 infection developed small bowel gangrene due to superior mesenteric artery thrombosis. He required resection of entire necrotic small bowel along with caecum causing ultra-short bowel syndrome. Reverse transcriptase-polymerase chain reaction (RT-PCR) done on the resected specimen was positive for COVID-19. He was maintained on individualized parenteral nutrition for 3 months. A living donor intestinal transplant was performed using 200 cm of ileum donated by the patient's father. The graft function was satisfactory and was not complicated with thrombosis, infection, reactivation of latent COVID-19 or rejection. He could be weaned off completely from parenteral nutrition by postoperative day 21. The donor had an uneventful recovery. Six month follow-up was satisfactory with the child achieving complete enteral autonomy as well as target goal nutrition. Thrombotic phenomena associated with COVID-19 infection can affect larger vessel-like superior mesenteric artery leading to small bowel gangrene. Intestine transplant could be done safely after 3 months of recovery from COVID-19 without any adverse outcomes. Further studies are required to establish optimal timing and safety of small bowel transplant in this situation.

Spontaneous diaphragmatic rupture as a complication following lung transplantation.

Spontaneous diaphragm rupture is a rare but potentially life-threatening condition, requiring urgent surgical intervention. Here we present two patients who developed spontaneous right hemidiaphragm rupture with abdominal visceral herniation into the thoracic cavity several days following bilateral lung transplantation, as an unusual complication. Both patients' surgeries were performed through bilateral anterior thoracotomies and were uneventful. There may be an association with this complication and patients suffering with emphysema, typically receiving donor lungs smaller than their native lungs, and with significant pretransplant exposure to steroids, factors that when combined may contribute to an increased risk of spontaneous diaphragmatic rupture in the absence of a significant precipitant. If a similar clinical picture is seen, teams managing lung transplant recipients should be aware of this potential complication and recognize the need for urgent intervention.

Perioperative risks of bariatric surgery among patients with and without history of solid organ transplant.

Bariatric surgery is effective among patients with previous transplant in limited case series. However, the perioperative safety of bariatric surgery in this patient population is poorly understood. Therefore, we assessed the safety of bariatric surgery among previous-transplant patients using a database that captures >92% of all US bariatric procedures. All primary, laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass procedures between 2017 and 2018 were identified from the MBSAQIP dataset. Patients with previous transplant (n = 610) were compared with patients without previous transplant (n = 321 447). Primary outcomes were 30 day readmissions, surgical complications, medical complications, and death. Multivariable logistic regression with predictive margins was used to compare outcomes. Previous transplant patients experienced higher incidence of readmissions (8.0% vs 3.5%), surgical complications (5.0% vs 2.7%), and medical complications (4.3% vs 1.5%). There was no difference in incidence of death (0.2% vs 0.1%). Among individual complications, there no statistical differences in intraabdominal leak, unplanned reoperation, myocardial infarction, or infectious complications. Baseline estimated glomerular filtration rate was found to be a strong moderator of primary outcomes, with the highest risk of complications occurring at the lowest baseline estimated glomerular filtration rate. Given the many long-term benefits of bariatric surgery among patients with previous transplant, our findings should not preclude this patient population from operative consideration.

Catastrophic sickling crisis in patient undergoing cardiac transplantation with sickle cell trait.

There is debate in the literature regarding management of patients with sickle cell trait (SCT) undergoing cardiac surgery, since it is recognized that cardiopulmonary bypass presents many precipitating risk factors for a sickling crisis. Despite this, many report successful outcomes without any modification to perioperative management. A 49-year-old woman with SCT (HbS 38%) with postpartum cardiomyopathy underwent cardiac transplantation. The patient was cooled to 34.0°C and retrograde cold blood cardioplegia was infused continuously. The cold ischemic time was 219 minutes and warm ischemic time 46 minutes. After weaning from bypass, she developed global cardiac dysfunction requiring veno-arterial extracorporeal membrane oxygenation. The circuit suddenly stopped, requiring emergency reinstitution of bypass; the circuit had clotted. Transesophageal-echocardiogram revealed thrombus within the left atrium and ventricle. There was no recovery of cardiac function and the patient developed multiorgan failure. At postmortem there was extensive myocardial infarction with evidence of widespread catastrophic intravascular red-cell sickling. This case highlights the danger of complacency in patients with SCT, offering a learning opportunity for the cardiothoracic community to highlight the most serious complication that can occur in this group of patients. We have learned that SCT and cardiac surgery is not a benign combination.

Enteric conversion after bladder-drained pancreas transplantation is not associated with worse allograft survival.

In the early experience of pancreas transplantation, bladder drainage was favored, but it often caused urologic, metabolic, and infectious complications that necessitated conversion to enteric drainage. Long-term graft survival after enteric conversion and the impact of time interval from transplantation to enteric conversion on graft survival is poorly understood. We studied all bladder-drained first-time pancreas transplantations performed at the University of Wisconsin from 1985 to 2000. Time to conversion was estimated with the Kaplan-Meier technique, whereas risk factors associated with conversion were estimated via a time-varying Cox proportional hazards model. Of 386 bladder-drained pancreata, 162 (41.9%) eventually required enteric conversion, 29 (17.9%) within the first year. Median time to conversion varied by indication: 0.68 years for surgical, 3.1 years for urologic, and 2.7 years for metabolic disorders. In a time-varying Cox model adjusting for donor and recipient factors, enteric conversion did not affect the risk of pancreas graft loss (hazard ratio [HR] 0.86, P = .26). Kidney survival was not associated with enteric conversion. When necessary due to symptoms or complications, enteric conversion of bladder-drained pancreata is safe and does not affect overall graft survival. This relationship appears to be true no matter when the conversion is performed.

C-peptide levels do not correlate with pancreas allograft failure: Multicenter retrospective analysis and discussion of the new OPT definition of pancreas allograft failure.

The OPTN Pancreas Transplantation Committee performed a multicenter retrospective study to determine if undetectable serum C-peptide levels correspond to center-reported pancreas graft failures. C-peptide data from seven participating centers (n = 415 graft failures for transplants performed from 2002 to 2012) were analyzed pretransplant, at graft failure, and at return to insulin. One hundred forty-nine C-peptide values were submitted at pretransplant, 94 at return to insulin, and 233 at graft failure. There were 77 transplants with two available values (at pretransplant and at graft failure). For recipients in the study with pretransplant C-peptide <0.75 ng/mL who had a posttransplant C-peptide value available (n = 61), graft failure was declared at varying levels of C-peptide. High C-peptide values at graft failure were not explained by nonfasting testing or by individual center bias. Transplant centers declare pancreas graft failure at varying levels of C-peptide and do not consistently report C-peptide data. Until February 28, 2018, OPTN did not require reporting of posttransplant C-peptide levels and it appears that C-peptide levels are not consistently used for evaluating graft function. C-peptide levels should not be used as the sole criterion for the definition of pancreas graft failure.

Failure of abdominal wall closure after intestinal transplantation: Identifying high-risk recipients.

Open abdomen and fascial dehiscence after intestinal transplantation increase morbidity. This study aims to identify recipient and donor factors associated with failure to achieve sustained primary closure (failed-SPC) of the abdomen after intestinal transplant. We conducted a single-center retrospective study of 96 intestinal transplants between 2013 and 2018. Thirty-eight (40%) were adult patients, and 58 were pediatric patients. Median age at transplantation was 36.0 and 5.8 years, respectively. Failed-SPC occurred in 31 (32%) patients. Identified risk factors of failed-SPC included preexisting enterocutaneous fistula (OR: 6.8, CI: 2.4-19.6, P = .0003), isolated intestinal graft (OR: 3.4, CI: 1.24-9.47, P = .02), male sex in adults (OR: 3.93, CI: 1.43-10.8, P = .009), and age over four years (OR: 6.22, CI: 1.7-22.7, P = .004). There was no association with primary diagnosis and prior transplant with failed-SPC. Donor-to-recipient size ratios did not predict failed-SPC. There was an association between failed-SPC and extended median hospital stay (100 vs 57 days, P = .007) and increased time to enteral autonomy in pediatric patients. There is a relationship between failed-SPC and a higher rate of laparotomy (OR: 21.4, CI: 2.78-178.2, P = .0003) and fistula formation posttransplant (OR: 11.4, CI: 2.83-45.84, P = .0005) in pediatric patients. Given inferior outcomes with failed-SPC, high-risk recipients require careful evaluation.

Living donor liver transplantation for biliary atresia: An analysis of 2085 cases in the registry of the Japanese Liver Transplantation Society.

Biliary atresia (BA) is the most common indication for liver transplantation (LT) in pediatric population. This study analyzed the comprehensive factors that might influence the outcomes of patients with BA who undergo living donor LT by evaluating the largest cohort with the longest follow-up in the world. Between November 1989 and December 2015, 2,085 BA patients underwent LDLT in Japan. There were 763 male and 1,322 female recipients with a mean age of 5.9 years and body weight of 18.6 kg. The 1-, 5-, 10-, 15-, and 20-year graft survival rates for the BA patients undergoing LDLT were 90.5%, 90.4%, 84.6%, 82.0%, and 79.9%, respectively. The donor body mass index, ABO incompatibility, graft type, recipient age, center experience, and transplant era were found to be significant predictors of the overall graft survival. Adolescent age (12 to <18 years) was associated with a significantly worse long-term graft survival rate than younger or older ages. We conclude that LDLT for BA is a safe and effective treatment modality that does not compromise living donors. The optimum timing for LT is crucial for a successful outcome, and early referral to transplantation center can improve the short-term outcomes of LT for BA. Further investigation of the major cause of death in liver transplanted recipients with BA in the long-term is essential, especially among adolescents.

Outcomes in Pancreas Transplantation With Exocrine Drainage Through a Duodenoduodenostomy Versus Duodenojejunostomy.

Until recently, pancreas transplantation has mostly been performed with exocrine drainage via duodenojejunostomy (DJ). Since 2012, DJ was substituted with duodenoduodenostomy (DD) in our hospital, allowing endoscopic access for biopsies. This study assessed safety profiles with DD versus DJ procedures and clinical outcomes with the DD technique in pancreas transplantation. DD patients (n = 117; 62 simultaneous pancreas-kidney [SPKDD ] and 55 pancreas transplantation alone [PTADD ] with median follow-up 2.2 years) were compared with DJ patients (n = 179; 167 SPKDJ and 12 PTADJ ) transplanted in the period 1998-2012 (pre-DD era). Postoperative bleeding and pancreas graft vein thrombosis requiring relaparotomy occurred in 17% and 9% of DD patients versus 10% (p = 0.077) and 6% (p = 0.21) in DJ patients, respectively. Pancreas graft rejection rates were still higher in PTADD patients versus SPKDD patients (p = 0.003). Hazard ratio (HR) for graft loss was 2.25 (95% CI 1.00, 5.05; p = 0.049) in PTADD versus SPKDD recipients. In conclusion, compared with the DJ procedure, the DD procedure did not reduce postoperative surgical complications requiring relaparatomy or improve clinical outcomes after pancreas transplantation despite serial pancreatic biopsies for rejection surveillance. It remains to be seen whether better rejection monitoring in DD patients translates into improved long-term pancreas graft survival.

Long-term outcomes of transmesenteric portal vein recanalization for the treatment of chronic portal vein thrombosis after pediatric liver transplantation.

Portal vein thrombosis (PVT) may occur at any time following liver transplantation. We describe our experience with portal vein recanalization in cases of thrombosis after liver transplantation. Twenty-eight children (5%) out of 566 liver transplant recipients underwent portal vein recanalization using a transmesenteric approach. All children received left hepatic segments, developed PVT, and had symptoms or signs of portal hypertension. Portal vein recanalization was performed via the transmesenteric route in all cases. Twenty-two (78.6%) patients underwent successful recanalization and stent placement. They received oral anticoagulants after the procedure, and clinical symptoms subsided. Symptoms recurred due to portal vein restenosis/thrombosis in seven patients. On an intention-to-treat basis, the success rate of the proposed treatment was 60.7%. Only 17 out of 28 children with posttransplant chronic PVT retained stent patency (primary + assisted) at the end of the study period. In cases of portal vein obstruction, the transmesenteric approach via minilaparotomy is technically feasible with good clinical and hemodynamic results. It is an alternative procedure to reestablish the portal flow to the liver graft that can be performed in selected cases and a therapeutic addition to other treatment strategies currently used to treat chronic PVT.

Islet alloautotransplantation: Allogeneic pancreas transplantation followed by transplant pancreatectomy and islet transplantation.

Simultaneous pancreas-kidney (SPK) transplantation is an important treatment option for patients with type 1 diabetes (T1D) and end-stage renal disease (ESRD). Due to complications, in up to 10% of patients, allograft pancreatectomy is necessary shortly after transplantation. Usually the donor pancreas is discarded. Here, we report on a novel procedure to rescue endocrine tissue after allograft pancreatectomy. A 39-year-old woman with T1D and ESRD who had undergone SPK transplantation required emergency allograft pancreatectomy due to bleeding at the vascular anastomosis. Islets were isolated from the removed pancreas allograft, and almost 480 000 islet equivalents were infused into the portal vein. The patient recovered fully. After 3 months, near-normal mixed meal test (fasting glucose 7.0 mmol/L, 2-hour glucose 7.5 mmol/L, maximal stimulated C-peptide 3.25 nmol/L, without insulin use in the preceding 36 hours) was achieved. Glycated hemoglobin while taking a low dose of long-acting insulin was 32.7 mmol/mol hemoglobin (5.3%). When a donor pancreas is lost after transplantation, rescue ß cell therapy by islet alloautotransplantation enables optimal use of scarce donor pancreata to optimize glycemic control without additional HLA alloantigen exposure.

A novel technique for en bloc kidney transplantation from infant donors with extremely low body weight by using the distal abdominal aorta as an outflow tract.

Pediatric kidney donors remain underutilized due to the high risk of postoperative thrombosis. To address this problem, we developed a novel en bloc kidney transplantation technique using donor thoracic aorta and the distal abdominal aorta as inflow and outflow tracts, respectively. Briefly, eight kidneys from deceased infant donors under five months old and with low body weight (1.9-4.9 kg) were transplanted en bloc into four pediatric and four adult patients. The donor's common iliac artery or external iliac artery was anastomosed to the recipient's distal external iliac artery or inferior epigastric artery, respectively, as an outflow tract. Recipients received basiliximab or antithymocyte globulin as induction therapy followed by tacrolimus, mycophenolate mofetil, and prednisone but without prophylactic anticoagulation. Delayed graft function was observed in one patient but was reversed at 90 days posttransplant. Two patients had urine leakage, which was cured by conservative treatment. Two recipients developed lung infections that eventually cleared. No patients experienced posttransplant vascular thrombosis. After 1-1.5 years of follow-up, all patients are well and have normal serum creatinine levels. In conclusion, this novel en bloc kidney transplantation technique using a modified arterial inflow and outflow tract can prevent vascular thrombosis and provide adequate graft function.

Aggressive infrainguinal revascularization in renal transplant patients is justifiable.

While studies demonstrate poor outcomes of lower extremity revascularization in patients with end-stage renal disease, little is known about results in renal transplant patients. We analyzed 2-year primary patency and limb salvage outcomes and associated risk factors of transplant (n = 202) and nontransplant patients (n = 25 274) in the Vascular Quality Initiative database undergoing infrainguinal bypass from 2003 to 2016. Multivariable Cox regression analysis and coarsened exact matching with many-to-one were used. Transplant patients were more likely to have critical limb ischemia and revascularization of more distal arteries and to receive vein conduits. Primary patency was similar between transplant and nontransplant patients at 1 year (80.8% vs 77.5%) and 2 years (67.9% vs 63.7%, P = .079). Amputation-free survival was higher for nontransplant patients (1 year: 82.4% vs 75.3%, 2 years: 68.8% vs 58.2%, P = .0060), although overall survival was equivalent (2 years: 84.6% vs 87.2%, 4 years: 75.9% vs 79.6%, P = .35). Risk factors for primary patency loss included being female, critical limb ischemia, prior bypass, and distal bypass. Age, diabetes, prior contralateral amputation, critical limb ischemia, prosthetic conduit, and more distal bypass were associated with limb loss. This is the largest series of infrainguinal revascularization in transplant patients. Outcomes for transplant patients are not inferior, and aggressive approaches at limb salvage are justifiable in appropriately selected patients.

Duodenal graft complications requiring duodenectomy after pancreas and pancreas-kidney transplantation.

Duodenal graft complications are poorly reported complications of pancreas transplantation that can result in graft loss. Excluding patients with early graft failure, after a median follow-up period of 126 months (range 23-198) duodenectomy was required in 14 of 312 pancreas transplants (4.5%). All patients were insulin-independent at the time of diagnosis. Reasons for duodenectomy included delayed duodenal graft perforation (n = 10, 71.5%) and refractory duodenal graft bleeding (n = 4, 28.5%). In patients with duodenal graft bleeding, a total duodenectomy was performed. In patients with duodenal graft perforation, preservation of a duodenal segment was possible in five patients but completion duodenectomy was necessary in one patient. After total duodenectomy, immediate enteric duct drainage was feasible in seven patients. In two patients, a pancreaticocutaneous fistula was created that was subsequently converted to enteric drainage in one patient. In the other patient, enteric fistulization occurred as a consequence of silent pressure perforation of the draining catheter on the ascending colon. After a mean follow-up period of 52 months (21-125), all patients were alive, well, and insulin-independent. An aggressive and timely surgical approach may permit graft rescue in patients with severe duodenal graft complications occurring after pancreas transplantation. Generalization of these results remains to be established.

Pediatric en bloc kidney transplantation from very small (≤10 kg) donation after circulatory death (versus brain death) donors: Single-center matched-pair analysis of 130 transplants.

En bloc kidney transplants (EBK) from very small pediatric donation after circulatory death (DCD) donors are infrequent because of the perception that DCD adversely impacts outcomes. We retrospectively studied 130 EBKs from donors ≤10 kg (65 consecutive DCD vs 65 donation after brain death [DBD] transplants; pair-matched for donor weight and terminal creatinine, and for preservation time). For DCD vs DBD, median donor weight was 5.0 vs 5.0 kg; median recipient age was 57 vs 48 years (P = .006). Graft losses from thrombosis (DCD, 5%; DBD, 7%) or primary nonfunction (DCD, 3%; DBD, 0%) were similar in both groups (P = .7). Delayed graft function rate was higher for DCD (25%) vs DBD (14%) (P = .2). Graft survival (death-censored) for DCD vs DBD at 5 years was 87% vs 91% (P = .3). Median estimated GFR (mL/min per 1.73 m2 ) was significantly lower for DCD recipients at 1 and 3 months; at 6 years it remained stable at 100 (DCD) and 99 (DBD). DCD impacted early posttransplant graft function, but did not appear to impart added risk for graft loss and long-term function. Very small (≤10 kg) DCD EBK donors should be considered as an option to augment the deceased kidney donor pool; larger studies with longer follow-up must confirm these findings.

Ureterocalicostomy with lower pole nephrectomy in a renal transplant: A case report.

As the number of kidney transplants continues to rise, so does the number and complexities of surgical-related complications, which may be associated with increased morbidity and potentially graft loss. Ureteral stenosis, the most prevalent urological complication, may require diverse techniques for surgical correction depending on several recipient and graft abnormalities. Here we report the surgical and clinical outcomes of a 62-year-old man with a posttransplant pyeloureterostomy stricture successfully treated with ureterocalicostomy after a lower pole nephrectomy. Although the resection of renal parenchyma may prevent a stenosis recurrence, surgeons can be reluctant to use this strategy due to the possible negative impact on renal function. We highlight some key steps of the surgical technique to prevent unnecessary allograft lesion and present short-term outcomes, suggesting that this rarely described procedure is a safe and effective alternative treatment for kidney transplant recipients with pyeloureterostomy stenosis.