Alloantibodies after simultaneous liver-kidney transplant: A story of primary nonfunction, retransplantation, and antibody-mediated rejection.

Simultaneous liver-kidney transplant (SLKT) in the presence of antihuman leukocyte antigen (HLA) donor-specific antibodies (DSA) is a well-accepted practice. Herein, we describe the evolution of alloantibodies in a patient who received an SLKT. The pre-SLKT serum sample showed multiple strong DSA. As expected, all DSA cleared in a sample collected 4 days after the SLKT. Because of the primary nonfunction of the liver in the SLKT, the patient had a second liver transplant 4 days later. An abrupt increase in DSA levels against the kidney was detected 10 days after the second liver transplant. These DSA were refractory to treatment, and the transplanted kidney was lost due to antibody-mediated rejection (AMR). A detailed study of the HLA epitopes recognized by DSA and, after normalization with third-party alloantibodies to address the effect of multiple transfusions and liver allograft neutralization, showed that the elimination of these antibodies depended on the HLA antigens expressed by the transplanted liver cells. The return of DSA after removal of the first transplanted liver was associated with AMR in the transplanted kidney.

Donation after circulatory death transplant outcomes using livers recovered by local surgeons.

Donation after circulatory death (DCD) liver transplantation (LT) outcomes have been attributed to multiple variables, including procurement surgeon recovery techniques. Outcomes of 196 DCD LTs at Mayo Clinic Arizona were analyzed based on graft recovery by a surgeon from our center (transplant procurement team [TPT]) versus a local procurement surgeon (non-TPT [NTPT]). A standard recovery technique was used for all TPT livers. The recovery technique used by the NTPT was left to the discretion of that surgeon. A total of 129 (65.8%) grafts were recovered by our TPT, 67 (34.2%) by the NTPT. Recipient age (p = 0.43), Model for End-Stage Liver Disease score (median 17 vs. 18; p = 0.22), and donor warm ischemia time (median 21.0 vs. 21.5; p = 0.86) were similar between the TPT and NTPT groups. NTPT livers had longer cold ischemia times (6.5 vs. 5.0 median hours; p < 0.001). Early allograft dysfunction (80.6% vs. 76.1%; p = 0.42) and primary nonfunction (0.8% vs. 0.0%; p = 0.47) were similar. Ischemic cholangiopathy (IC) treated with endoscopy occurred in 18.6% and 11.9% of TPT and NTPT grafts (p = 0.23). At last follow-up, approximately half of those requiring endoscopy were undergoing a stent-free trial (58.3% TPT; 50.0% NTPT; p = 0.68). IC requiring re-LT in the first year occurred in 0.8% (n = 1) of TPT and 3.0% (n = 2) of NTPT grafts (p = 0.23). There were no differences in patient (hazard ratio [HR], 1.95; 95% confidence interval [CI], 0.76-5.03; p = 0.23) or graft (HR, 1.99; 95% CI, 0.98-4.09; p = 0.10) survival rates. Graft survival at 1 year was 91.5% for TPT grafts and 95.5% for NTPT grafts. Excellent outcomes can be achieved using NTPT for the recovery of DCD livers. There may be an opportunity to expand the use of DCD livers in the United States by increasing the use of NTPT.

Increased access to liver transplantation for patients with acute on chronic liver failure after implementation of Share 35 Rule: An analysis from the UNOS database.

INTRODUCTION AND OBJECTIVES: Acute on chronic liver failure (ACLF), leads to high mortality. These patients are at risk of being delisted for liver transplantation (LT). Emerging data shows 1y post-transplant survival of 80-92%. The Share 35 (S35) policy was implemented to prioritize patients with MELD ≥35 on the LT waitlist. Our aim was to compare the LT outcomes of ACLF patients as a result of S35. MATERIALS AND METHODS: Data from the UNOS scientific registry were used to classify ACLF patients using the NACSELD criteria. For the analyses, data were divided into two eras; 2 years before S35 (Era 1) and 2 years after S35 (Era 2). Waitlist status was classified into categories: Transplanted, Death or Too Sick to Transplant and Still Waiting/Other. LT cumulative incidence between the populations in the eras was calculated using Fine and Gray's method. A proportional hazards model was used to investigate the era effect on cumulative incidence of LT. RESULTS: 46,861 patients were reviewed, of which 817 had ACLF. 366 patients (mean MELD: 37.1) were identified in Era 1 and 451 patients (mean MELD: 37.3) in Era 2. We found that ACLF patients were more likely to receive a liver transplant in Era 2 (p=0.0074). In both eras, transplanted patients had a significantly higher survival than those who were not transplanted (p<0.0001). CONCLUSIONS: Our study shows that S35 improved LT rate for ACLF suggesting that there should be broader recognition of ACLF and early transplantation should be pursued.

Simultaneous liver-kidney transplantation from donation after cardiac death donors: an updated perspective.

Outcomes of both donation after cardiac death (DCD) liver and kidney transplants are improving. Experience in simultaneous liver-kidney transplant (SLK) using DCD donors, however, remains limited. In an updated cohort (2010-2018), outcomes of 30 DCD SLK and 131 donation after brain death (DBD) SLK from Mayo Clinic Arizona and Mayo Clinic Minnesota were reviewed. The Model for End-Stage Liver Disease score was lower in the DCD SLK group (23 vs 29, P = .01). Kidney delayed graft function (DGF) rates were similar between the 2 groups (P = .11), although the duration of DGF was longer for DCD SLK recipients (20 vs 4 days, P = .01). Liver allograft (93.3% vs 93.1%, P = .29), kidney allograft (93.3% vs 93.1%, P = .91), and patient (96.7% vs 95.4%, P = .70) 1-year survival rates were similar. At 1 year, there were no differences in the estimated glomerular filtration rate (57.7 ± 18.2 vs 56.3 ± 17.7, P = .75) or progression of fibrosis (ci) on protocol kidney biopsy (P = .67). A higher incidence of biliary complications was observed in the DCD SLK group, with ischemic cholangiopathy being the most common (10.0% vs 0.0%, P = .03). The majority of biliary complications resolved with endoscopic management. With appropriate selection, DCD SLK recipients can have results equivalent to those of DBD SLK recipients.

Clinical Outcomes of Portosystemic Shunts on the Outcome of Liver Transplantation.

Spontaneous portosystemic shunts (SPSSs) have been associated with worse clinical outcomes in the pre-liver transplantation (LT) setting, but little is known about their post-LT impacts. Our aim was to compare LT candidates with and without SPSSs and assess the impact of SPSSs on patient mortality and graft survival in the post-LT setting. Patients 18 years or older with abdominal imaging done prior to LT were included. Exclusion criteria were the presence of pre-LT surgical shunts, LT indications other than cirrhosis, and combined solid organ transplantations. SPSSs were classified as absent, small, or large according to their maximum diameter (8 mm). Multiple variables that could influence the post-LT course were extracted for analysis. Patient and graft survival were estimated using the Kaplan-Meier method and were compared between groups using a log-rank test. The project received institutional review board approval. We extracted data from 326 patients. After comparing patients without SPSS or with small or large SPSSs, no statistical difference was found for overall patient survival: no SPSS (n = 8/63), reference; small SPSS (n = 18/150), hazard ratio (HR), 1.05 (95% confidence interval [CI], 0.45-2.46); and large SPSS (n = 6/113), HR, 0.60 (95% CI, 0.20-1.78); P = 0.20. Also, no difference was found for graft survival: no SPSS (n = 11/63), reference; small SPSS (n = 21/150), HR, 0.80 (95% CI, 0.38-1.70); large SPSS (n = 11/113), HR, 0.59 (95% CI, 0.25-1.40); P = 0.48. Similarly, no statistical significance was found for these variables when comparing if the graft used was procured from a donation after circulatory death donor versus a donation after brain death donor. In conclusion, the previously described association between SPSSs and worse clinical outcomes in pre-LT patients seems not to persist once patients undergo LT. This study suggests that no steps to correct SPSS intraoperatively are necessary.

Hospitalizations for Cardiovascular Disease After Liver Transplantation in the United States.

Cardiovascular disease (CVD) is a leading cause of post-liver transplant death, and variable care patterns may affect outcomes. We aimed to describe epidemiology and outcomes of inpatient CVD care across US hospitals. Using a merged data set from the 2002-2011 Nationwide Inpatient Sample and the American Hospital Association Annual Survey, we evaluated liver transplant patients admitted primarily with myocardial infarction (MI), stroke (cerebrovascular accident [CVA]), congestive heart failure (CHF), dysrhythmias, cardiac arrest (CA), or malignant hypertension. Patient-level data include demographics, Charlson comorbidity index, and CVD diagnoses. Facility-level variables included ownership status, payer-mix, hospital resources, teaching status, and physician/nursing-to-bed ratios. We used generalized estimating equations to evaluate patient- and hospital-level factors associated with mortality. There were 4763 hospitalizations that occurred in 153 facilities (transplant hospitals, n = 80). CVD hospitalizations increased overall by 115% over the decade (P < 0.01). CVA and MI declined over time (both P < 0.05), but CHF and dysrhythmia grew significantly (both P < 0.03); a total of 19% of hospitalizations were for multiple CVD diagnoses. Transplant hospitals had lower comorbidity patients (P < 0.001) and greater resource intensity including presence of cardiac intensive care unit, interventional radiology, operating rooms, teaching status, and nursing density (all P < 0.01). Transplant and nontransplant hospitals had similar unadjusted mortality (overall, 3.9%, P = 0.55; by diagnosis, all P > 0.07). Transplant hospitals had significantly longer overall length of stay, higher total costs, and more high-cost hospitalizations (all P < 0.05). After risk adjustment, transplant hospitals were associated with higher mortality and high-cost hospitalizations. In conclusion, CVD after liver transplant is evolving and responsible for growing rates of inpatient care. Transplant hospitals are associated with poor outcomes, even after risk adjustment for patient and hospital characteristics, which may be attributable to selective referral of certain patient phenotypes but could also be related to differences in quality of care. Further study is warranted.

"Mirror, Mirror on the Wall" Pediatric liver transplantation in the case of situs inversus totalis with a disrupted inferior vena cava.

We present the unique case of a 15-month-old male born with biliary atresia and situs inversus totalis and disrupted inferior vena cava who underwent a successful liver transplantation. The patient had previously undergone a failed Kasai procedure and presented with persistent hyperbilirubinemia. The patient was transplanted with a left lateral segment donor having standard arterial anatomy. Technical considerations included identifying completely replaced arterial anatomy in the recipient from the superior mesenteric artery and creating a branch patch between the gastroduodenal artery and HA, anastomosing the donor left hepatic vein to confluences of the donor left, middle, and right hepatic veins, using a "lazy-S" configuration of portal vein anastomosis, and suspending the allograft to the abdominal wall. Post-operatively, his liver function tests and total bilirubin normalized and he progressed to tolerating an oral diet with tube-feed supplementation.

Immunosuppression in pediatric liver transplant recipients: Unique aspects.

Pediatric liver transplantation has experienced improved outcomes over the last 50 years. This can be attributed in part to establishing optimal use of immunosuppressive agents to achieve a balance between minimizing the risks of allograft rejection and infection. The management of immunosuppression in children is generally more complex and can be challenging when compared with the use of these agents in adult liver transplant patients. Physiologic differences in children alter the pharmacokinetics of immunosuppressive agents, which affects absorption, distribution, metabolism, and drug excretion. Children also have a longer expected period of exposure to immunosuppression, which can impact growth, risk of infection (bacterial, viral, and fungal), carcinogenesis, and likelihood of nonadherence. This review discusses immunosuppressive options for pediatric liver transplant recipients and the unique issues that must be addressed when managing this population. Further advances in the field of tolerance and accommodation are needed to relieve the acute and cumulative burden of chronic immunosuppression in children. Liver Transplantation 23 244-256 2017 AASLD.

Glucose homeostasis after simultaneous pancreas and kidney transplantation: a comparison of subjects with C-peptide-positive non-type 1 diabetes mellitus and type 1 diabetes mellitus.

BACKGROUND: While simultaneous pancreas kidney transplant (SPKTx) is a therapeutic option for patients with type 1 diabetes (T1DM) and renal failure, few centers offer SPKTx to "select" non-T1DM patients. To address concerns that existing insulin resistance may limit the benefits of the pancreas allograft among non-T1DM, we compared several indices of glucose homeostasis, in "select" non-T1DM and T1DM patients who received SPKTx. METHODS: Criteria for "select" non-T1DM included the following: positive C-peptide, BMI <30 kg/m(2) , treatment with oral agents before insulin initiation, and insulin at <1 unit/kg/d. We compared several indices of glucose homeostasis within 1 yr post-SPKTx among seven "select" patients with non-T1DM and nine patients with T1DM with similar age, BMI, and immunosuppression. Measurements of insulin resistance included the following: homeostatic model, insulin sensitivity index, and insulin-glucose ratio; insulin secretion measures included the following: corrected insulin response. RESULTS: Non-T1DM had similar pre-transplant metabolic (fasting glucose, HbA1c, blood pressure, and lipid) parameters to the T1DM cohort. There were no significant differences in the various measures of insulin resistance and secretion between T1DM and "select" non-T1DM patients. CONCLUSION: Our results suggest SPKTx should be considered in the therapeutic armamentarium among carefully select non-T1DM with features of minimal insulin resistance; however, a larger cohort with longer follow-up is needed to confirm our results.

Outcomes of a Large Series of Laparoscopic Ventral Hernia Repairs after Liver Transplantation.

BACKGROUND: The hernia defects that develop in liver transplant recipients tend to be complex. Unfortunately, there is a paucity of data to guide post-transplant hernia management. Our goal was to evaluate the outcomes following laparoscopic ventral hernia repair (LVHR) in liver transplant recipients. METHODS: A retrospective review of a prospectively kept database of liver transplant patients at a single tertiary healthcare facility was completed. All patients between 2007 and 2020 who underwent LVHR for a hernia at their transplant incision site were included. The primary outcome studied was hernia recurrence. Secondary outcomes included time-to-hernia repair, complications, and length of stay (LOS). RESULTS: There were 89 patients who met inclusion criteria. 82% were male, mean age was 60 years, and mean body mass index was 30.2 kg/m2. 94.4% were on tacrolimus and 36% on mycophenolate mofetil. Median time-to-hernia repair was 16 months with a mean mesh size of 743 cm2 and length of stay of 3.7 days. None required conversion to an open operation. Postoperative complications included ileus (20.2%), acute kidney injury (11.2%), pneumonia (6.7%), and bleeding requiring re-operation (1.1%). Hernia-related complications included chronic suture site pain (1.1%), seroma requiring intervention (3.3%), surgical site infection (3.3%), nonoperative mesh infection (1.1%), and mesh infection requiring explantation (1.1%). Median follow-up was 23 months. Hernia recurrence occurred in 4.5% and no predictive variables for recurrence were identified. CONCLUSIONS: Although the hernia defects that develop in liver transplant recipients are complex and their comorbidities significant, LVHR can safely and effectively repair these defects with low rates of recurrence and complications.

Outcomes of endoscopic retrograde cholangiography and percutaneous transhepatic biliary drainage in liver transplant recipients with a Roux-en-Y biliary-enteric anastomosis.

Backgrounds/Aims: Data regarding outcomes of endoscopic retrograde cholangiography (ERC) in liver transplant (LT) recipients with biliary-enteric (BE) anastomosis are limited. We report outcomes of ERC and percutaneous transhepatic biliary drainage (PTBD) as first-line therapies in LT recipients with BE anastomosis. Methods: All LT recipients with Roux-BE anastomosis from 2001 to 2020 were divided into ERC and PTBD subgroups. Technical success was defined as the ability to cannulate the bile duct. Clinical success was defined as the ability to perform cholangiography and therapeutic interventions. Results: A total of 36 LT recipients (25 males, age 53.5 ± 13 years) with Roux-BE anastomosis who underwent biliary intervention were identified. The most common indications for a BE anastomosis were primary sclerosing cholangitis (n = 14) and duct size mismatch (n = 10). Among the 29 patients who initially underwent ERC, technical success and clinical success were achieved in 24 (82.8%) and 22 (75.9%) patients, respectively. The initial endoscope used for the ERC was a single balloon enteroscope in 16 patients, a double balloon enteroscope in 7 patients, a pediatric colonoscope in 5 patients, and a conventional reusable duodenoscope in 1 patient. Among the 7 patients who underwent PTBD as the initial therapy, six (85.7%) achieved technical and clinical success (p = 0.57). Conclusions: In LT patients with Roux-BE anastomosis requiring biliary intervention, ERC with a balloon-assisted enteroscope is safe with a success rate comparable to PTBD. Both ERC and PTBD can be considered as first-line therapies for LT recipients with a BE anastomosis.

Declining Medicare reimbursement in abdominal transplantation from 2000 to 2021.

BACKGROUND: The Centers for Medicare and Medicaid Services is a major payer for abdominal transplant services. Reimbursement reductions could have a major impact on the transplant surgical workforce and hospitals. Yet government reimbursement trends in abdominal transplantation have not been fully characterized. METHODS: We performed an economic analysis to characterize changes in inflation-adjusted trends in Medicare surgical reimbursement for abdominal transplant procedures. Using the Medicare Fee Schedule Look-Up Tool, we performed a procedure code-based surgical reimbursement rate analysis. Reimbursement rates were adjusted for inflation to calculate overall changes in reimbursement, overall year-over-year, 5-year year-over-year, and compound annual growth rate from 2000 to 2021. RESULTS: We observed declines in adjusted reimbursement of common abdominal transplant procedures, including liver (-32.4%), kidney with and without nephrectomy (-24.2% and -24.1%, respectively), and pancreas transplant (-15.2%) (all, P < .05). Overall, the yearly average change for liver, kidney with and without nephrectomy, and pancreas transplant were -1.54%, -1.15%, -1.15%, and -0.72%. Five-year annual change averaged -2.69%, -2.35%, -2.64%, and -2.43%, respectively. The overall average compound annual growth rate was -1.27%. CONCLUSION: This analysis depicts a worrisome reimbursement pattern for abdominal transplant procedures. Transplant surgeons, centers, and professional organizations should note these trends to advocate sustainable reimbursement policy and to preserve continued access to transplant services.

Spontaneous middle lobe torsion: An institutional case series.

Objective: Lobar torsion is a rare occurrence in which a portion of the lung is twisted on its bronchovascular pedicle. The vast majority are observed in the acute postoperative period often following right upper lobectomy. Spontaneous middle lobe torsion independent of pulmonary resection is exceptionally rarer; fewer than 15 cases have been recorded. We present an institutional case series of 2 patients postorthotopic liver transplantation who developed spontaneous middle lobe torsion due to large pleural effusions. Methods: We provide the medical course as well as intraoperative techniques for our 2 patients along with a review of the literature. Results: Both patients in this case series underwent orthotopic liver transplant complicated postoperatively by a large pulmonary effusion. Patient one developed an abdominal hematoma requiring evacuation and repair, after which he developed progressive shortness of breath. Bronchoscopy revealed a right middle lobe obstruction; upon thoracotomy, 180-degree torsion with widespread necrosis was evident and the middle lobe was removed. He is doing well to date. Patient 2 experienced postoperative pleural effusion and mucus plugging; computed tomography revealed abrupt middle lobe arterial occlusion prompting urgent operative intervention. Again, the middle lobe was grossly ischemic and dissection revealed a 360-degree torsion around the pedicle. It was resected. He is doing well to date. Conclusions: As the result of its rarity, radiographic and clinical diagnosis of spontaneous pulmonary lobar torsion is challenging; a high index of suspicion for spontaneous middle lobe torsion must be maintained to avoid delays in diagnosis. Prompt surgical intervention is essential to improve patient outcomes.

Utilization of Veno-Arterial Extracorporeal Life Support for Acute Respiratory Distress Syndrome After Liver Transplant.

In this report, we present a case of successful long-term salvage of a patient with transfusion-related acute lung injury associated with acute respiratory distress syndrome immediately after a liver transplant. The patient was a 29-year-old man with end-stage liver disease due to sclerosing cholangitis who underwent liver transplant. After organ reperfusion, there was evidence of liver congestion, acidosis, coagulopathy, and acute kidney injury. He received 61 units of blood products. Continuous renal replacement therapy was initiated intraoperatively. On arrival to the intensive care unit, the patient was on high-dose pressors, and the patient developed respiratory failure and was immediately placed on veno-arterial extracorporeal membrane oxygenation via open femoral exposure. The patient presented with severe coagulopathy and early allograft dysfunction; therefore, no systemic heparin was administered and no thrombotic events occurred. He required extracorporeal membrane oxygenation support until posttransplant day 4, when resolution of the respiratory and cardiac dysfunction was noted. At 2 years after liver transplant, the patient has normal liver function, normal cognitive function, and stage V chronic kidney disease. We conclude that extracorporeal membrane oxygenation is a valuable therapeutic approach in patients with cardiorespiratory failure after liver transplant.

Solid Organ Transplantation From SARS-CoV-2-infected Donors to Uninfected Recipients: A Single-center Experience.

BACKGROUND: The risk of donor-derived severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in solid organ (heart, lung, liver, kidney, pancreas, and intestine) transplant recipients is poorly understood. Since hematogenous transmission of SARS-CoV-2 has not been documented to date, nonlung solid organs might be suitable for transplantation since they likely portend a low risk of viral transmission. METHODS: Abdominal solid organs from SARS-CoV-2-infected donors were transplanted into uninfected recipients. RESULTS: Between April 18, 2021, and October 30, 2021, we performed transplants of 2 livers, 1 simultaneous liver and kidney, 1 kidney, and 1 simultaneous kidney and pancreas from SARS-CoV-2-infected donors into 5 uninfected recipients. None of the recipients developed SARS-CoV-2 infection or coronavirus disease 2019, and when tested, allograft biopsies showed no evidence of SARS-CoV-2 RNA. CONCLUSIONS: Transplanting nonlung organs from SARS-CoV-2-infected donors into uninfected recipients demonstrated no evidence of virus transmission.

Anesthesia for combined cardiac surgery and liver transplant.

OBJECTIVE: To describe aspects of anesthesia for combined cardiac surgery and orthotopic liver transplant (OLT). DESIGN: Retrospective case series. SETTING: Hospital with cardiac surgery and liver transplant programs. PARTICIPANTS: Nine patients between September 1998 and July 2006. INTERVENTION: Combined cardiac surgery and OLT. MEASUREMENT AND MAIN RESULTS: Demographic and outcome data were recorded for each patient. Multiple intraoperative parameters were collected at baseline, after induction of anesthesia, after cardiac surgery, and after OLT. Five patients underwent combined OLT and coronary artery bypass graft (CABG) surgery. Four patients underwent combined OLT and aortic valve replacement (AVR) to relieve aortic stenosis. One of these 4 patients also had a saphenous vein graft to the left anterior descending artery. The CABG/OLT patients had hypertension, diabetes, or both, and multiple coronary arteries were affected although ejection fraction was preserved. The 1 death in this group was unrelated to a coronary event. The AVR/OLT patients had aortic stenosis that met American Heart Association guidelines for AVR. One death, within 24 hours of surgery, was associated with severe pulmonary artery hypertension. The median transfusion volumes were 12 units of packed red blood cells, 22 units of fresh frozen plasma, and 30 units of platelets. Three of the 9 patients required renal replacement therapy postoperatively. The median duration of intubation was 2 days, and length of stay in the intensive care unit was 5.5 days. CONCLUSION: Combined cardiac and OLT surgery is complex and serious morbidity occurs, but successful outcomes are attainable.

Robot Assisted Renal Allograft Nephrectomy: Initial Case Series and Description of Technique.

OBJECTIVE: To evaluate the outcomes and perioperative complication rates following robot- assisted transplant nephrectomy ((RATN). METHODS: All patients who underwent RATN at our institution were included. No exclusion criteria were applied. Clinical records were retrospectively reviewed and reported. This included preoperative, intraoperative, and postoperative outcomes. Complications were reported utilizing the Clavien-Dindo classification system. Descriptive statistics were reported using frequencies and percentages for categorical variables, means and standard deviation for continuous variables. RESULTS: Between July 2014 and April 2018, 15 patients underwent RATN. Most patients had the transplant in the right iliac fossa (13/15). Ten patients underwent a concomitant procedure. The total operative time for the entire cohort was 336 (±102) minutes (including cases who had concomitant procedures) and 259 (±46 minutes) when cases with concomitant procedures were excluded. Mean estimated blood loss was 383 (±444) mL. Postoperatively, 3 patients required blood transfusion. Average hospital stay was 4 (±2.7) days. Most patients had finding consistent with graft rejection on final pathology. There were 5 complications; 3 of which were minor (grade 2 = 2 and grade 3 = 1); one patient had a wound infection requiring dressing (3A) and one patient died due to pulmonary embolism following discharge. Limitations include small series and retrospective nature of the study. CONCLUSION: This case series demonstrate that RATN is technically feasible. With continued experience and larger case series, the robotic approach may provide a minimally invasive alternative to open allograft nephrectomy.

Unexplained and prolonged perioperative hypotension after orthotopic liver transplantation: undiagnosed systemic mastocytosis.

Arterial vasodilation is common in end-stage liver disease, and systemic hypotension often may develop, despite an increase in cardiac output. During the preparation for and the performance of orthotopic liver transplantation, expected and transient hypotension may be caused by induction agents, anesthetic agents, liver mobilization, or venous clamping. A mild decrease of the already low systemic vascular resistance is often observed, and intermittent use of short-acting agents for vasopressor support is not uncommon. In this report, we describe a patient with unexpected and prolonged hypotension due to vasodilation during and after orthotopic liver transplantation. The preoperative end-stage liver disease evaluation, intraoperative events, and intensive care unit course were reviewed, and no cause for the vasodilation and prolonged hypotension was evident. The explant pathology report was later available and showed systemic mastocytosis. We hypothesize that the unexpected hypotension and vasodilation were caused by mast cell degranulation and its systemic effects on arterial tone.