The Current State of Liver Transplantation in the United States: Perspective From American Society of Transplant Surgeons (ASTS) Scientific Studies Committee and Endorsed by ASTS Council.

This article is a review of the salient points and a future prospective based on the 2014 Organ Procurement and Transplantation Network (OPTN)/Scientific Registry of Transplant Recipients (SRTR) liver donation and transplantation data report recently published by the American Journal of Transplantation. Emphasis of our commentary and interpretation is placed on data relating to waitlist dynamics, organ utilization rates, the impact of recent advances in the treatment of hepatitis C, and the increases in end-stage renal disease among liver transplant candidates. Finally, we share our vision on potential areas of innovation that are likely to significantly improve the field of liver transplantation in the near future.

Machine Perfusion of Donor Livers for Transplantation: A Proposal for Standardized Nomenclature and Reporting Guidelines.

With increasing demand for donor organs for transplantation, machine perfusion (MP) promises to be a beneficial alternative preservation method for donor livers, particularly those considered to be of suboptimal quality, also known as extended criteria donor livers. Over the last decade, numerous studies researching MP of donor livers have been published and incredible advances have been made in both experimental and clinical research in this area. With numerous research groups working on MP, various techniques are being explored, often applying different nomenclature. The objective of this review is to catalog the differences observed in the nomenclature used in the current literature to denote various MP techniques and the manner in which methodology is reported. From this analysis, we propose a standardization of nomenclature on liver MP to maximize consistency and to enable reliable comparison and meta-analyses of studies. In addition, we propose a standardized set of guidelines for reporting the methodology of future studies on liver MP that will facilitate comparison as well as clinical implementation of liver MP procedures.

Adenosine Increases Hepatic Artery Flow in Liver Transplant Recipients: A Pilot Study.

BACKGROUND: The aim of this study was to assess the effect of low-dose adenosine on hepatic artery flow (HAF) when administered intraoperatively by continuous infusion. MATERIALS AND METHODS: Between January 2009 and August 2009, 74 patients underwent orthotopic liver transplantation (OLT). Ten patients were enrolled for adenosine treatment, and 64 non-study patients served as controls. After arterial reperfusion, a 16-G central venous catheter was placed in the gastroduodenal artery, and adenosine was continuously infused at doses ranging from 0.7 to 2.8 µg/kg/min for 30 min. HAF and portal vein flow were measured using a transit time flow meter before adenosine infusion, during infusion, and 10 min after infusion. Liver function tests were monitored routinely, duplex ultrasonography was performed on postoperative day 1, and the hepatic artery resistive index measured. The patients were followed for 1 year. RESULTS: Adenosine significantly increased HAF at doses from 0.7 to 2.8 µg/kg/min. The smallest increase in HAF was 24% above the baseline; in 80% of patients, the increase in HAF was >50% of the baseline values. In 2 patients, HAF was increased by >300%. The dosing started at 0.7 µg/kg/min, and 6 of 10 patients responded. Three patients required an increase to 1.4 µg/kg/min. Doses >2.8 µg/kg/min did not further increase HAF. One patient showed a minimal response regardless of the dose. There were no differences between the adenosine group and control group with respect to liver function (aspartate aminotransferase, alanine aminotransferase, total bilirubin, and International Normalized Ratio), platelet count on POD2, hepatic artery resistive index, and post-transplant length of stay, intensive care days, or 1-year patient survival rates. CONCLUSIONS: This pilot study established that adenosine administered directly into the hepatic artery produces a similar effect on HAF in cadaveric liver transplant recipients to that found in the laboratory without producing systemic side effects.

Comparing Normothermic Machine Perfusion Preservation With Different Perfusates on Porcine Livers From Donors After Circulatory Death.

The utilization of normothermic machine perfusion (NMP) may be an effective strategy to resuscitate livers from donation after circulatory death (DCD). There is no consensus regarding the efficacy of different perfusates on graft and bile duct viability. The aim of this study was to compare, in an NMP porcine DCD model, the preservation potential of three different perfusates. Twenty porcine livers with 60 min of warm ischemia were separated into four preservation groups: cold storage (CS), NMP with Steen solution (Steen; XVIVO Perfusion Inc., Denver, CO), Steen plus red blood cells (RBCs), or whole blood (WB). All livers were preserved for 10 h and reperfused to simulate transplantation for 24 h. During preservation, the NMP with Steen group presented the highest hepatocellular injury. At reperfusion, the CS group had the lowest bile production and the worst hepatocellular injury compared with all other groups, followed by NMP with Steen; the Steen plus RBC and WB groups presented the best functional and hepatocellular injury outcomes, with WB livers showing lower aspartate aminotransferase release and a trend toward better results for most parameters. Based on our results, a perfusate that contains an oxygen carrier is most effective in a model of NMP porcine DCD livers compared with Steen solution. Specifically, WB-perfused livers showed a trend toward better outcomes compared with Steen plus RBCs.

Association between liver transplant center performance evaluations and transplant volume.

There has been increased oversight of transplant centers and stagnation in liver transplantation nationally in recent years. We hypothesized that centers that received low performance (LP) evaluations were more likely to alter protocols, resulting in reduced rates of transplants and patients placed on the waiting list. We evaluated the association of LP evaluations and transplant activity among liver transplant centers in the United States using national Scientific Registry of Transplant Recipients data (January 2007 to July 2012). We compared the average change in recipient and candidate volume and donor and patient characteristics based on whether the centers received LP evaluations. Of 92 eligible centers, 27 (29%) received at least one LP evaluation. Centers without an LP evaluation (n = 65) had an average increase of 9.3 transplants and 14.9 candidates while LP centers had an average decrease of 39.9 transplants (p < 0.01) and 67.3 candidates (p < 0.01). LP centers reduced the use of older donors, donations with longer cold ischemia, and donations after cardiac death (p-values < 0.01). There was no association between the change in transplant volume and measured performance (R(2) = 0.002, p = 0.91). Findings indicate a strong association between performance evaluations and changes in candidate listings and transplants among liver transplant centers, with no measurable improvement in outcomes associated with reduction in transplant volume.

Intrahepatic blood flow redistribution after temporary occlusion of the middle hepatic vein during right lobe liver donation: report of a case.

INTRODUCTION: One of the critical factors that influence graft function after live donor liver transplantation is the presence or absence of global or sectorial liver congestion. Many authors advocate for routine middle hepatic vein (MHV) reconstruction because it is often difficult to determine when the MHV or one of its major branches have functional significance. Predictive tests to assess hemodynamic and functional significance of the MHV and its tributaries are still under study. CASE REPORT: We have described a novel intraoperative manipulation and Doppler ultrasonographic evaluation that led to the decision to include the MHV with the right lobe graft.

Split liver transplantation using Hemiliver graft in the MELD era: a single center experience in the United States.

Under the "sickest first" Model for End-Stage Liver Disease (MELD) allocation, livers amenable to splitting are most often allocated to patients unsuitable for split liver transplantation (SLT). Our experience with SLT using hemilivers was reviewed. From April 2004 to June 2012, we used 25 lobar grafts (10 left lobes and 15 right lobes) for adult-sized recipients. Twelve recipients were transplanted with primary offers, and 13 were transplanted with leftover grafts. Six grafts were shared with other centers. The data were compared with matched whole liver grafts (n = 121). In 92% of donors, the livers were split in situ. Hemiliver recipients with severe portal hypertension had a greater graft-to-recipient weight ratio than those without severe portal hypertension (1.96% vs. 1.40%, p < 0.05). Hemiliver recipients experienced biliary complications more frequently (32.0% vs. 10.7%, p = 0.01); however, the 5-year graft survival for hemilivers was comparable to whole livers (80.0% vs. 81.5%, p = 0.43). The secondary recipients with leftover grafts did not have increased incidences of graft failure (p = 0.99) or surgical complications (p = 0.43) compared to the primary recipients. In conclusion, while routine application is still controversial due to various challenges, hemiliver SLT can achieve excellent outcomes under the MELD allocation.

Combined intestine and kidney transplantation in a patient with encapsulating peritoneal sclerosis: case report.

Encapsulating peritoneal sclerosis (EPS) is a rare but devastating complication of peritoneal dialysis characterized by fibrosis and calcification of the intestine that, in severe cases, can progress to intestinal failure and total parenteral nutrition dependency. Medical and surgical interventions carry a poor prognosis in these patients. We describe a case of a 36-year-old female with end-stage kidney disease and severe EPS not amenable to surgical intervention who underwent a combined intestinal and kidney transplantation. At 3 years posttransplantation, the patient has normal intestinal and kidney function. This represents, to our knowledge, the first report of severe EPS and end-stage kidney disease treated with a combined transplant.

Case-matched comparison of perioperative outcomes after surgical treatment of sigmoid diverticulitis in solid organ transplant recipients versus immunocompetent patients.

AIM: To compare the perioperative outcomes following surgery for sigmoid diverticulitis in transplant recipients and immunocompetent patients. METHOD: Solid organ transplant recipients operated on for sigmoid diverticulitis from 1995 to 2010 were case-matched to immunocompetent patients based on surgical procedure, American Society of Anesthesiologists classification, Hinchey score, elective vs urgent surgery, age ± 10 years and year of surgery ± 5 years. Demographics, clinical presentation and perioperative outcomes were assessed. RESULTS: Of 5329 consecutive patients undergoing heart, lung, kidney and liver transplantation since 1995, 51 (0.6%) underwent surgery for diverticulitis between 1995 and 2010 with 14% mortality and 45% morbidity. Urgent surgery in 37/51 patients [Hartmann's procedure 28, sigmoidectomy with diverting ileostomy 8, loop ileostomy 1 (9 cases within 2 months after transplantation)] was associated with significantly increased postoperative mortality (19%vs 0%, P = 0.01), increased morbidity (51%vs 24%, P = 0.03) and longer mean hospital stay (19 vs 13 days, P = 0.1) when compared with immunocompetent patients. Four patients undergoing urgent surgery had suffered previous episodes of diverticulitis treated nonoperatively. Elective surgery was associated with no mortality in 14 transplant recipients (nine sigmoidectomy with diverting ileostomy, five sigmoidectomy without diversion) or in immunocompetent controls. Following elective procedures, transplant recipients had similar morbidity and increased hospital stay (29% and 9.6 vs 6.5 days, P = 0.2, respectively). Permanent stoma rates and postoperative morbidity after stoma takedown were comparable in the two groups. All living patients except one (kidney) retained their graft function. CONCLUSIONS: Urgent surgery for sigmoid diverticulitis in transplant recipients is associated with worse postoperative outcomes when compared with immunocompetent patients, unlike elective surgery. Future studies will need to clarify the role of early surgery after the first diverticulitis episode.

Use of tissue plasminogen activator in liver transplantation from donation after cardiac death donors.

Ischemic-type biliary stricture (ITBS) occurs in up to 50% after liver transplantation (LT) from donation after cardiac death (DCD) donors. Thrombus formation in the peribiliary microcirculation is a postulated mechanism. The aim was to describe our experience of tissue plasminogen activator (TPA) administration in DCD-LT. TPA was injected into the donor hepatic artery on the backtable (n = 22). Two recipients developed ITBS including one graft failure. Although excessive postreperfusion bleeding was seen in 14 recipients, the amount of TPA was comparable between those with and without excessive bleeding (6.4 ± 2.8 vs. 6.6 ± 2.8 mg, p = 0.78). However, donor age (41 ± 12 vs. 29 ± 9 years, p = 0.02), donor BMI (26.3 ± 5.5 vs. 21.7 ± 3.6 kg/m(2) , p = 0.03), previous laparotomy (50% vs. 0%, p = 0.02) and lactate after portal reperfusion (6.3 ± 4.6 vs. 2.8 ± 0.9 mmol/L, p = 0.005) were significantly greater in recipients with excessive bleeding. In conclusion, the use of TPA may lower the risk of ITBS-related graft failure in DCD-LT. Excessive bleeding may be related to poor graft quality and previous laparotomy rather than the amount of TPA. Further studies are needed in larger population.

Adult-to-adult living donor liver transplantation using left lobes: the importance of surgical modulations on portal graft inflow.

BACKGROUND: Due to the shortage of available cadaveric organs, living donor liver transplantation (LDLT) has been recently applied extensively in adults. The use of the left lobe should be encouraged because of donor safety, but frequently the metabolic requirements of severely cirrhotic patients are great and subsequent graft dysfunction is encountered after transplantation. The importance of increased portal inflow to the graft in previously severely cirrhotic patients and other hemodynamic changes in LDLT using left lobes are still under debate, as are the surgical modulations to correct them. In this study, we have reported an initial series of adult-to-adult LDLT using left lobes, underlining the hemodynamic changes encountered during the transplant and the surgical modulations we applied to correct them. METHODS: Eight adult recipients underwent left lobe liver transplantation from living donors. Portal vein pressure and central venous pressure were measured before and after surgical modulation. RESULTS: We encountered four cases of small-for-size syndrome. Two patients were retransplanted; the other two died. Seventy-five percent of our recipients survived and 50% did not require further surgery. CONCLUSION: Surgical portal inflow modulation should be considered in cases of left lobe liver transplantation between adults.

Association of emergence of HLA antibody and acute rejection in intestinal transplant recipients: a possible evidence of acute humoral sensitization.

Development of HLA antibody has been associated with chronic allograft failure in kidney recipients. We tested HLA antibody in posttransplant sera of intestinal recipients: 126 sera from 28 pediatric recipients were tested for HLA antibody by flow PRA (f-PRA). Median age was 1.1 years (0.44-17). Graft types included isolated intestine (n = 6), liver and intestine (n = 3), modified multivisceral (n = 3), and multivisceral grafts (n = 16). Greater than 10% of either class I (CI) or class II (CII) f-PRA was considered positive, and >30% strongly positive. Five of 28 patients had positive f-PRA in multiple samples; the remaining 23 had either no positive or only one positive sample. Three patients had strongly positive f-PRA. Patients with multiple positive samples were recipients of two modified multivisceral and three multivisceral grafts. Only one of these patients had a positive PRA pretransplant. Cytotoxic cross-match at transplant was negative for all. The three with strongly positive f-PRA showed significant episodes of rejection around the time of positive samples. One of them who persistently had f-PRA value >80% (from day 13-113) died of refractory rejection. The other two had f-PRA of 76% and 53% during the early postoperative course with associated episodes of rejection. F-PRA value decreased with rejection therapy. Only one of the 23 patients (4%) with negative f-PRA had an episode of rejection around the time of sample collection. Development of HLA antibody after intestinal transplantation seems to have significant association with acute rejection episodes.

Analysis of risk factors for the development of posttransplant lymphoprolipherative disorder among 119 children who received primary intestinal transplants at a single center.

UNLABELLED: Posttransplant lymphoproliferative disorder (PTLD) is a well-known complication after pediatric transplantation. We analyzed all potential risk factors to assess patient and graft outcomes of 119 children who received intestinal transplantations. MATERIALS AND METHODS: Between August 1994 and March 2005, 119 patients underwent cadaveric intestinal transplantation. Their median age at transplant was 1.4 years (range: 0.6-17), median weight was 9.5 kg (range: 4.7-67), and 57% were boys. The median follow-up among 49 ongoing survivors was 41 months (range: 4-121). All PTLD cases were biopsy proven. In the past 5 years, treatment included antiviral therapy, immunosuppression withdrawal, and use of rituximab. RESULTS: The incidence of PTLD was 11.8% (14/119). No patient experienced graft failure secondary to PTLD, while two patients died from PTLD (14.2%). The PTLD group was divided into an early onset group (<4 months, 6 of 14; 42.8%) and a late onset group (>2 years, 8 of 14; 57.2%). No patient experienced PTLD between 4 months and 2 years after transplantation. The use of OKT3 was the only significant risk factor for the development of PTLD. No factor was specifically associated with the early versus late development of PTLD. CONCLUSIONS: The only factor associated with a significantly higher risk of PTLD was the use of OKT3 to treat a rejection episode. Finally, since the the introduction of anti-CD20 antibodies as part of the treatment protocol for PTLD, the risk of death due to PTLD appears to have become manageably low.

Hepatic hilum management in 250 liver-multivisceral procurements.

An accurate in vivo preparation of the hepatic hilum is a fundamental prerequisite for a successful multiorgan transplantation. Our preferred technique in this surgical setting is in vivo procurement in the heart-beating donor. This technique allows an effective exposition of the hilum structures and recognition of anatomical vascular variants, particularly those of the hepatic artery. Also, the cold ischemia time is drastically reduced, and the back-table preparation is left to a minimum. In this article we show the results of a consecutive series of 250 procurements.

Fatal cytomegalovirus necrotising enteritis in a small bowel transplantation adult recipient with low pp65 antigenaemia levels.

Although advances in immunosuppressive therapy have led to increased survival of solid organ transplantation recipients, it is well established that current protocols have been associated with an increased risk of developing tissue-invasive infections. In particular, cytomegalovirus still represents an important cause of morbidity. We report a case of cytomegalovirus infection involving the graft ileum with documented necrotising enteritis that developed after small bowel transplantation. The patient, a 56-year-old Caucasian female with a postsurgery short bowel syndrome, underwent a small bowel transplantation. Immunosuppression was maintained by combination of tacrolimus, steroids and daclizumab. Both the donor and the recipient were serologically negative for cytomegalovirus IgG. Nevertheless, ganciclovir prophylaxis was given for 21 days after surgery, as standard procedure. On hospital day 174, routine pp65 antigenaemia resulted positive (14/200,000 peripheral blood leukocytes). The patient was asymptomatic and preemptive ganciclovir therapy was instituted. In the following 3 days, due to a cytomegalovirus antigenaemia increase, ganciclovir was changed to foscarnet with subsequent virological response (7/200,000 peripheral blood leukocytes, on day 181). Two days later, the patient complained of acute abdominal pain and she underwent surgery for the diagnosis. Since the intraoperative findings consisted of a diffuse acute purulent peritonitis, the intestinal graft, together with native rectum, was removed. Biopsy specimens showed evidence of tissue-invasive cytomegalovirus infection. Postsurgery, the patient developed septic shock and died on day 198 as a consequence of multiple organ failure.

Outcome in right living related liver transplantation with branch-patch arterial reconstruction.

cRight lobe living liver transplantation is being performed worldwide with increased frequency. Difficult arterial reconstructions are often encountered because of small diameter or discrepancy between arterial stumps. The risk of arterial thrombosis is reported as high as 26%: microsurgical techniques have reduced this rate below 2%, increasing warm ischemia time. We have developed a new branch patch technique in living related liver transplantation using the donor cystic artery to create an enlarged patch anastomosis that enables increase in the vessel's diameter and therefore greater inflow to the liver. We have followed 8 patients treated with this technique. After more than 1 year (mean follow-up: 636 days) we did not observe any arterial thrombosis by Doppler ultrasound performed every 3 months. The mean resistance index was 0.68 (0.57-0.83-). Three patients died with functional graft without signs of thrombosis. We believe that the cystic artery branch patch technique is feasible in all cases. It is fast (mean time: 6.2 min), it allows a shorter warm ischemia time, and there is no increased risk of thrombosis.

Multivisceral harvest with in vivo technique: methods and results.

Multivisceral transplants are gaining acceptance worldwide for patients with chronic gastrointestinal failure with or without irreversible total parenteral nutrition (TPN)-related liver failure. We describe our experience with nine multivisceral harvests reporting our in vivo technique. Multivisceral grafts included stomach, duodenum, pancreas, small bowel, and part of large intestine with or without the liver. After a careful evaluation of the liver and the bowel, we isolated the superior mesenteric artery origin. Then we identified the distal part of the graft isolating the middle colic vein and stapling the transverse colon to its left. After esophagus isolation and stapling, we mobilized the graft, starting from the spleen to the pancreaticoduodenal block, near the celiac trunk. After cross-clamping and cold perfusion, we created an aortic patch including the superior mesenteric artery and celiac trunk as a multivisceral harvest without the liver. A total hepatectomy is added for a liver multivisceral graft. We harvested four multivisceral grafts without the liver and five multivisceral grafts with the liver. We performed seven multivisceral transplants on adult recipients, four without the liver and three with the liver, as well as two liver and one isolated small bowel transplants. Postreperfusion hemostasis was always satisfactory with a mean ischemia time of 6.5 hours. Four recipients died: there was one intraoperative death due to disseminated intravascular coagulopathy. Another patient underwent graftectomy 1 day after transplantation due to vascular thrombosis. In conclusion, our in vivo technique allows a shorter ischemia time with a minimal postreperfusion bleeding and reduced production of lymphatic ascites, without jeopardizing organ function.

Living donor liver transplantation in adult patients: our experience.

INTRODUCTION: Living donation in adult liver transplantation (LDLTx) is an important resource because of the waiting list growth. We started a living donor program to overcome the shortage of cadaveric sources. PATIENTS: From May 2001 to May 2003, 36 patients underwent LDLTx: 27 received a right lobe, 8 received a left lobe, and 1 received segments II and III. RESULTS: The 1-year actuarial survival rate was 77.7%, with a mean follow-up, in survivors, of 754 +/- 248 days. Eleven of 27 (40.7%) right lobe recipients died. Among left graft recipients, 3 patients died (33%). We undertook retransplantation in 4 cases, because of 2 "small for size" syndrome, 1 late hepatic artery thrombosis, and 1 early portal vein thrombosis. After a period of 797 days, all 36 donors returned to a normal social and working life. Two donors, who underwent right lobe donation, experienced major complications: 1 case of biliary stenosis, treated by stenting, and 1 case of biliary leak from the cut surface of the liver, requiring laparotomy and abscess drainage. Left lobe donors developed no complications. CONCLUSIONS: LDLTx has a learning curve for experienced liver transplantation surgeons. Our last 18 cases showed better survivals than the first 18 (9 deaths vs 5), even if, in the latter group, we transplanted 8 left livers. In our experience, LDLTx of a left liver graft has an increased risk of "small for size syndrome," but patients, both donors and recipients, report improved outcomes.