Impact of segmental grafts on pediatric liver transplantation--a review of the United Network for Organ Sharing Scientific Registry data (1990-1996)

Are split liver grafts a suitable option in high-risk liver transplant recipients?

PURPOSE OF REVIEW

To assess the outcomes of split liver transplantation (SLT) in adults and children and evaluate its role in high-risk recipients with a high model for end-stage liver disease (MELD) score, an urgent indication or requiring retransplantation.

RECENT FINDINGS

Split liver grafts in general have equivalent long-term survival outcomes to whole grafts despite an increase in biliary complications. Recent success and technical advances have encouraged use of these grafts in high-risk recipients. Split liver grafts can be used successfully in recipients with a high MELD score if there is adequate weight-matching. There are mixed results in urgent indication recipients and for retransplantation such that use in this group of patients remains controversial.

SUMMARY

SLT addresses donor shortages by facilitating the transplant of two recipients from the same donor liver. By using careful donor and recipient selection criteria, SLT can achieve equivalent long-term outcomes to whole grafts. These grafts have been used successfully in recipients with a high MELD score, but should be used selectively in urgent indication recipients and for retransplantation.

Postoperative Doppler Ultrasonography in Liver Transplantation

BACKGROUND

Doppler ultrasonography plays an important role in the postoperative management of liver transplantation. We present our initial experiences evaluating liver transplants with the use of postoperative Doppler sonography.

METHODS

In our hospital, we performed 20 liver transplantations from July 2014 to October 2016. Among 20 patients, we performed 15 deceased-donor liver transplantations (DDLTs) and 5 living-donor liver transplantations (LDLTs). For deceased donors, inferior vena cava anastomoses were performed with the use of the piggyback technique, and for living donors, modified right grafts were used with middle hepatic vein reconstruction by Dacron graft. In the intensive care unit, we performed Doppler ultrasound at least once a day and at every clinical need. We checked hepatic blood flow by means of Doppler ultrasound.

RESULTS

Eighteen patients underwent Doppler ultrasonography once a day up to postoperative day 6. Of the patients who received LDLT, 2 patients underwent Doppler ultrasonography twice a day because the operator was concerned about the hepatic artery anastomosis. Findings on Doppler ultrasound showed no abnormal wave form in hepatic artery, portal vein and hepatic veins. No patient had abnormal findings on angiographic computerized tomography. There was 1 graft failure in 20 recipients. The graft failure was primary nonfunction, and retransplantation was done. During the hospitalizations, there were no vascular complications.

CONCLUSIONS

Doppler ultrasonography can be used to evaluate postoperative vascular complications in liver transplant patients. When the operator checks postoperative Doppler ultrasonography, it is possible to differentiate between patients, and it may help to detect the vascular complications earlier.

Conformational Fingerprinting Using Monoclonal Antibodies (on the Example of Angiotensin I-Converting Enzyme-ACE)

During the past 30 years my laboratory has generated 40+ monoclonal antibodies (mAbs) directed to structural and conformational epitopes on human ACE as well as ACE from rats, mice and other species. These mAbs were successfully used for detection and quantification of ACE by ELISA, Western blotting, flow cytometry and immunohistochemistry. In all these applications mainly single mAbs were used. We hypothesized that we can obtain a completely new kind of information about ACE structure and function if we use the whole set of mAbs directed to different epitopes on the ACE molecule. When we finished epitope mapping of all mAbs to ACE (and especially, those recognizing conformational epitopes), we realized that we had obtained a new tool to study ACE. First, we demonstrated that binding of some mAbs is very sensitive to local conformational changes on the ACE surface—due to local denaturation, inactivation, ACE inhibitor or mAbs binding or due to diseases. Second, we were able to detect, localize and characterize several human ACE mutations. And, finally, we established a new concept—conformational fingerprinting of ACE using mAbs that in turn allowed us to obtain evidence for tissue specificity of ACE, which has promising scientific and diagnostic perspectives. The initial goal for the generation of mAbs to ACE 30 years ago was obtaining mAbs to organ-specific endothelial cells, which could be used for organ-specific drug delivery. Our systematic work on characterization of mAbs to numerous epitopes on ACE during these years has lead not only to the generation of the most effective mAbs for specific drug/gene delivery into the lung capillaries, but also to the establishment of the concept of conformational fingerprinting of ACE, which in turn gives a theoretical base for the generation of mAbs, specific for ACE from different organs. We believe that this concept could be applicable for any glycoprotein against which there is a set of mAbs to different epitopes.

Outcomes of Technical Variant Liver Transplantation versus Whole Liver Transplantation for Pediatric Patients: A Meta-Analysis

Objective

To overcome the shortage of appropriate-sized whole liver grafts for children, technical variant liver transplantation has been practiced for decades. We perform a meta-analysis to compare the survival rates and incidence of surgical complications between pediatric whole liver transplantation and technical variant liver transplantation.

Methods

To identify relevant studies up to January 2014, we searched PubMed/Medline, Embase, and Cochrane library databases. The primary outcomes measured were patient and graft survival rates, and the secondary outcomes were the incidence of surgical complications. The outcomes were pooled using a fixed-effects model or random-effects model.

Results

The one-year, three-year, five-year patient survival rates and one-year, three-year graft survival rates were significantly higher in whole liver transplantation than technical variant liver transplantation (OR = 1.62, 1.90, 1.65, 1.78, and 1.62, respectively, p<0.05). There was no significant difference in five-year graft survival rate between the two groups (OR = 1.47, p = 0.10). The incidence of portal vein thrombosis and biliary complications were significantly lower in the whole liver transplantation group (OR = 0.45 and 0.42, both p<0.05). The incidence of hepatic artery thrombosis was comparable between the two groups (OR = 1.21, p = 0.61).

Conclusions

Pediatric whole liver transplantation is associated with better outcomes than technical variant liver transplantation. Continuing efforts should be made to minimize surgical complications to improve the outcomes of technical variant liver transplantation.

Current concepts in pediatric liver transplantation

Liver transplantation is the definitive treatment for end-stage liver disease in both children and adults. Advances over the last 2 decades have resulted in excellent patient and graft survival rates in what were previously cases of fatal disorders. These developments have been due to innovations in surgical technique, increased surgical experience, refinements in immunosuppressive regimens, quality improvements in intraoperative anesthetic management, better understanding of the pathophysiology of the liver diseases, and better preoperative and postoperative care. Remarkably, the use of split-liver and living-related liver transplantation surgical techniques has helped mitigate the well-recognized national organ shortage. This review will discuss the major aspects of pediatric liver transplantation as it pertains to indication for transplantation, recipient selection and listing for orthotopic liver transplantation, pre-orthotopic liver transplantation care of children, optimal timing of orthotopic liver transplantation, surgical technical considerations, postoperative care and complications, and patient and graft survival outcomes.

Incidence, impact, and treatment of portal and hepatic venous complications following pediatric liver transplantation: a single-center 12 year experience

PVT or PVS and HVOO are known causes of graft and patient loss after pediatric liver transplantation. Increased incidences of these complications have been reported in partial livers including DDSLT or LDLT. From 1997 to 2008, 241 consecutive pediatric patients received 271 hepatic grafts at a single center. Median follow-up is 1856 days. Surgical technique, demographics, lab values, and radiologic imaging procedures were obtained utilizing OTTR to evaluate the relationship of portal and hepatic complications with risk factors, patient and graft survival. Grafts were composed of 115/271 (42.4%) partial livers of which 90 (33.2%) were DDSLT and 25 (9.2%) LDLT. Of 271 patients, 156 (57.6%) received whole-sized grafts. There were six PVC in five patients with one patient requiring retransplantation (0.34%) and no patient deaths. Utilizing all three hepatic vein orifices on the recipient hepatic vena cava and the donor hepatic vein cut short enables a wide hepatic outflow tract unlikely to twist. None of the 241 patients developed early or late complications of the hepatic vein. None of the last 128 consecutive patients who received 144 grafts over seven and a half yr have developed either early or late complications of the hepatic or portal vein. Partial-graft actuarial survival was similar to whole-graft survival (87.2% vs. 85.3% at one yr; 76.6% vs. 80.2 at three yr; p = 0.488). Likewise, patient survival was similar between partial grafts and whole grafts (93.8% vs. 93.1% at one yr; 89.8% vs. 87.2% at three yr; p = 0.688) with median follow-up of 1822 (+/-1334) days. Patients receiving partial livers were significantly younger and smaller than patients receiving whole livers (p < 0.001). Portal and hepatic venous complications may have negative effects on patient or graft survival after pediatric liver transplantation. In our series, there was one graft and no patient loss related to portal or hepatic venous complications after pediatric liver transplantation over 12 yr.

Predictors of survival following liver transplantation in infants: a single-center analysis of more than 200 cases

BACKGROUND

Infants (<12 months) who require liver transplantation (LTx) represent a particularly challenging and understudied group of patients.

METHODS

This retrospective study aimed to describe a large single-center experience of infants who received isolated LTx, illustrate important differences in infants versus older children, and identify pretransplant factors which influence survival. More than 25 pre-LTx demographic, laboratory, and operative variables were analyzed using the Log-rank test and Cox proportional hazards model.

RESULTS

Between 1984 and 2006, 216 LTx were performed in 186 infants with a mean follow-up time of 62 months. Median age at LTx was 9 months, the majority had cholestatic liver disease, were hospitalized pre-LTx, and received whole grafts. Leading indications for re-LTx (n=30) included vascular complications (43%) and graft nonfunction (40%), whereas leading causes of death were sepsis and multiorgan failure. One-, 5-, and 10-year graft and patient survivals were 75%/72%/68% and 79%/77%/75%, respectively. Relative to older pediatric recipients, infants had worse overall patient survival (P=0.05). The following were significant univariate predictors of graft loss: age less than 6 months and reduced cadaveric grafts; and of patient loss: age less than 6 months, calculated CrCl less than 90, pre-LTx hospitalization, pre-LTx mechanical ventilation, repeat LTx, infants transplanted for reasons other than cholestatic liver disease, and patients transplanted between 1984 and 1994.

CONCLUSIONS

Long-term outcomes for infants undergoing LTx are excellent and have improved over time. As the largest, single-center analysis of LTx in infants, this study elucidates a unique set of predictors that can aid in medical decision making.

Split-liver transplantation: an underused resource in liver transplantation

Split-liver transplantation is an efficient tool to increase the number of liver grafts available for transplantation. More than 15 years after its introduction only the classical splitting technique has reached broad application. Consequently children are benefiting most from this possibility. Full-right full-left splitting for two adult recipients has been shown to work but is hampered mainly by the dangers of small-for-size transplantation. A solution to this last problem would completely change the scope of split-liver transplantation. Organ allocation systems and collaboration between centers play a crucial role in the chances to let suitable patients profit from this valuable source of extra grafts.

Analysis of recent pediatric orthotopic liver transplantation outcomes indicates that allograft type is no longer a predictor of survivals

Two strategies to increase the donor allograft pool for pediatric orthotopic liver transplantation (OLT) are deceased donor segmental liver transplantation (DDSLT) and living donor liver transplantation (LDLT). The purpose of this study is to evaluate outcomes after use of these alternative allograft types. Data on all OLT recipients between February 2002 and December 2004 less than 12 years of age were obtained from the United Network for Organ Sharing database. The impact of allograft type on posttransplant survivals was assessed. The number of recipients was 1260. Of these, 52% underwent whole liver transplantation (WLT), 33% underwent DDSLT, and 15% underwent LDLT. There was no difference in retransplantation rates. Immediate posttransplant survivals differed, with WLT patients having improved 30-day patient survivals compared to DDSLT and LDLT patients (P = 0.004). Although unadjusted 1-year patient survivals were better for WLT versus DDSLT (P = 0.01), after risk adjustment, 1-year patient survivals for WLT (94%), DDSLT (91%), and LDLT (93%) were similar (P values > 0.05). Unadjusted allograft survivals were better for WLT and LDLT in comparison with DDSLT (P = 0.009 and 0.018, respectively); however, after adjustment, these differences became nonsignificant (all P values > 0.05). For patients < or = 2 years of age (n = 833), the adjusted 1-year patient and allograft survivals were also similar (all P values > 0.05). In conclusion, in the current era of pediatric liver transplantation, WLT recipients have better immediate postoperative survivals. By 1 year, adjusted patient and allograft survivals are similar, regardless of the allograft type.

Impact of graft type on outcome in pediatric liver transplantation: a report From Studies of Pediatric Liver Transplantation (SPLIT)

OBJECTIVE

To examine the outcome of technical variant liver transplant techniques relative to whole organ liver transplantation in pediatric liver transplant recipients.

BACKGROUND

Technical variant liver transplant techniques comprising split, reduced, and live-donor liver transplantation evolved to address the need for timely and size appropriate grafts for pediatric recipients.

METHODS

Analysis of data from the Studies of Pediatric Liver Transplantation (SPLIT) registry, a multicenter database of 44 North American pediatric liver transplant programs. The outcome (morbidity and mortality) of each of the technical variants were compared with that of whole organ recipients.

RESULTS

Data were available on 2192 transplant recipients (1183 whole, 261 split, 388 reduced, and 360 live donor). Recipients of all technical variant graft type were significantly younger than whole organ recipients, but on average spent 2.3 months less on the waiting list. Thirty-day post-transplant morbidity was increased for each type of technical variant relative to whole organ (45.1% whole, 66.7% split, 65.5% reduced, 51.9% live-donor). Biliary complications (30 day: 7.5% whole, 18.8% split, 16% reduced, 17.5% live-donor) and portal vein thrombosis (30 day: 3.6% whole, 8% split, 8% reduced, 7.5% live-donor) were more common in all technical variant types. Graft type was an independent predictor of graft loss (death or retransplantation) in a multivariate analysis. Split and reduced (relative risk = 1.74 and 1.77, respectively) grafts had a worse outcome when compared with whole organ recipients.

CONCLUSIONS

Technical variant techniques expand the pediatric donor pool and reduce time from listing to transplant, but they are associated with increased morbidity and mortality.

Outcomes of primary liver cancer in children: an appraisal of experience

INTRODUCTION

Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) are the most common primary liver cancers in children. Recent advances in management of pediatric liver cancer have improved disease-specific survival (DSS). This is a review of our experience with childhood liver malignancy over the past 3 decades.

MATERIALS AND METHODS

A retrospective chart review from 1975 to 2005 identified patients who were 18 years old or younger with a histologically confirmed diagnosis of primary liver cancer. Patients were staged according to the Children's Cancer Group and Pediatric Oncology Group (CCG/POG) system. Patients were followed up prospectively through clinic visits and mail correspondence. Standard statistical methods were used for comparison, risk, and survival analyses.

RESULTS

Fifty-two patients were confirmed to have primary liver cancers, where 24 (46%) patients had HB, 22 (42%) had HCC, 3 (6%) had sarcomas, and 3 (6%) had other histologies. Mean ages at presentation for HB and HCC were 3.2 and 13.1 years old, respectively. The most common presentations were abdominal mass (67%) and pain (40%). Most patients underwent major liver resection (n = 45, 87%), including: lobectomy (n = 25, 48%), and trisegmentectomy (n = 11, 21%). Three patients underwent liver transplantation (n = 3, 6%) for advanced local disease. Forty-five (87%) received primary or neoadjuvant and/or adjuvant chemotherapy. Patients had the following CCG/POG stages: I (n = 31, 60%), II (n = 6, 11.5%), III (n = 9, 17%), and IV (n = 6, 11.5%). Complete gross resection (stage I and II) was achieved in 37 (71%) patients. The perioperative mortality and morbidity rates were 0% and 29%, respectively. Patients with complete resection had significantly better 5-year DSS and median survival compared with incomplete gross resection: 62% vs 9% and 216 vs 18 months, P < .001. Patients treated during the period 1995-2005 had better 5-year DSS and median survival compared with those treated during 1975-1994: 68% vs 32% and 117 vs 27 months, P = .032. All 3 patients who underwent transplantation for conventionally unresectable disease are alive without disease recurrence (follow-up period, 1-15 years).

CONCLUSION

Complete resection of the pediatric primary liver tumors remains the cornerstone of treatment to achieve cure. Major liver resection can be performed with minimal perioperative mortality and morbidity. Patients with HB appeared to have better survival compared with patients with HCC, and there was significant improvement in the DSS of children treated in the recent decade. Liver transplantation in conjunction with chemotherapy may have an increasing role in the management of locally advanced primary liver cancers.

Predictors of clinical outcome in children undergoing orthotopic liver transplantation for acute and chronic liver disease

The current United Network for Organ Sharing (UNOS) policy is to allocate liver grafts to pediatric patients with chronic liver disease based on the pediatric end-stage liver disease (PELD) scoring system, while children with fulminant hepatic failure may be urgently listed as Status 1a. The objective of this study was to identify pre-transplant variables that influence patient and graft survival in those children undergoing LTx (liver transplantion) for FHF (fulminant hepatic failure) compared to those patients transplanted for extrahepatic biliary atresia (EHBA), a chronic form of liver disease. The UNOS Liver Transplant Registry was examined for pediatric liver transplants performed for FHF and EHBA from 1987 to 2002. Variables that influenced patient and graft survival were assessed using univariate and multivariate analysis. Kaplan-Meier analysis of FHF and EHBA groups revealed that 5 year patient and graft survival were both significantly worse (P < 0.0001) in those patients who underwent transplantation for FHF. Multivariate analysis of 29 variables subsequently revealed distinct sets of factors that influenced patient and graft survival for both FHF and EHBA. These results confirm that separate prioritizing systems for LTx are needed for children with chronic liver disease and FHF; additionally, our findings illustrate that there are unique sets of variables which predict survival following LTx for these two groups.

Long-term graft outcome of pediatric liver transplantation in Copenhagen: analysis of the first 51 cases

BACKGROUND

Graft loss after liver transplantation remains a significant problem, especially in pediatric patients. The aim of this study was to assess our initial series of pediatric liver transplantation and to identify the risk factors that influence graft outcome.

METHODS

The first 51 transplantations were analyzed retrospectively. All transplantations were stratified into three groups according to graft type (full-size, reduced-size, and living-related-donor graft). Survival data of the grafts were stratified and multivariate analysis conducted with respect to preoperative and surgical factors.

RESULTS

Seventeen of all the transplants were full-size grafts and 34 technical-variant grafts (27 reduced-size grafts from cadavers and 7 living-related-donor grafts). The overall graft survival rates were 65, 62 and 53% at 1, 3 and 5 years, respectively. Twenty-three of 51 grafts (45%) were lost. Poor status of the recipients (hospitalization or intensive care unit care before surgery), a retransplanted graft, and a reduced-size graft were independent risk factors for graft failure. With experience, overall graft survival has improved significantly and the differences in graft survival between graft types have disappeared.

CONCLUSIONS

To improve graft survival after pediatric liver transplantation, the timely referral of potential recipients to the transplant team and employing a meticulous technique during the operation, particularly for the technical-variant graft, are required.

Live donor liver transplantation

With ever-increasing demand for liver replacement, supply of organs is the limiting factor and a significant number of patients die while waiting. Live donor liver transplantation has emerged as an important option for many patients, particularly small pediatric patients and those adults that are disadvantaged by the current deceased donor allocation system. Ideally there would be no need to subject perfectly healthy people in the prime of their lives to a potentially life-threatening operation to procure transplantable organs. Donor safety is imperative and cannot be compromised regardless of the implication for the intended recipient. The evolution of split liver transplantation is the basis upon which live donor transplantation has become possible. The live donor procedures are considerably more complex than whole organ decreased donor transplantation and there are unique considerations involved in the assessment of any specific recipient and donor. Donor selection and evaluation have become highly specialized. The critical issue of size matching is determined by both the actual size of the donor graft and the recipient as well as the degree of recipient portal hypertension. The outcomes after live donor liver transplantation have been at least comparable to those of deceased donor transplantation. Nevertheless, all efforts should be made to improve deceased donor donation so as to minimize the need for live donors. Transplant physicians, particularly surgeons, must take responsibility for regulating and overseeing these procedures.

Endovascular Treatment of Acute Portal Vein Thrombosis After Liver Transplantation in a Child

Although operative techniques in hepatic transplantation have reduced the time and mortality on waiting lists, the rate of vascular complications associated with these techniques has increased. Stenosis or thrombosis of the portal vein is an infrequent complication, and if present, surgical treatment is considered the traditional management. This article describes a case of acute portal vein thrombosis after liver transplantation from a living donor to a child managed by percutaneous techniques.

Endovascular treatment of stenosis between hepatic vein and inferior vena cava following liver transplantation in a child: a case report

The liver transplantation technique advances have allowed the endovascular treatment of stenosis between hepatic vein and inferior vena cava, and this has become an established and widely acceptable method for the treatment of patients with end-stage liver disease. However, in spite of the advances in the surgical technique of liver transplantation there is relatively still a high incidence of postoperative complications, especially those related to vascular complications. One technical variant of orthotopic liver transplantation is the piggyback technique with conservation of the recipient vena cava, which is anastomosed to the graft hepatic veins. As a consequence of the increased number of liver transplants in children, there is a higher demand for endovascular treatment of vascular stenosis, such as those at the level of the hepatic veins. This leads to more consistent experience of endovascular treatment of the surgical vascular complications following liver transplantation. This article describes the case of a child submitted to liver transplantation with reduced graft (left lateral segment) who presented stenosis of the anastomosis between the hepatic vein and IVC 6 months later which was successfully treated by PTA.

Survival among pediatric liver transplant recipients: impact of segmental grafts

Segmental liver transplantation with living donor (LD), reduced cadaveric (Reduced), and split cadaveric (Split) allografts has expanded the availability of size-appropriate organs for pediatric recipients. The relevance of recipient age to the selection of graft type has not been fully explored, but could offer the potential to maximize recipient outcome and donor utilization. We conducted a retrospective cohort study among children 12 years of age or less utilizing the United Network of Organ Sharing (UNOS) database. Cox proportional-hazards analysis was used to explore the association of recipient age and graft type to graft and patient survival. Among children <1 year of age and those 1 to 2 years of age, 3-year LD graft survival was superior to whole cadaveric (CAD) organs, Split grafts, and Reduced grafts (for children <1 year of age: 79.4 vs. 61.5, 66.0, and 61.1%, respectively, P = .0003; and for children 1-2 years of age: 79.2 vs 66.9, 57.1, and 63.9%, respectively, P = .02). However, in children 3 to 12 years of age, after controlling for multiple donor and recipient factors, LD grafts failed to offer a survival advantage (hazard ratio = .61; 95% confidence interval = .37-1.02) compared to CAD organs. In an adjusted analysis examining patient survival, there appeared to be minimal association between recipient age and graft type. Much of the difference in graft survival could be attributed to events in the perioperative period. In conclusion, LD liver transplantation provides improved graft survival in children 2 years of age or less.

Studies of Pediatric Liver Transplantation: 2002 update. An overview of demographics, indications, timing, and immunosuppressive practices in pediatric liver transplantation in the United States and Canada

Studies of Pediatric Liver Transplantation (SPLIT) was initiated in 1995 for the purpose of collecting comprehensive data from children undergoing liver transplantation. As of May 31, 2002, 1761 children were registered in SPLIT from 38 participating centers in the United States and Canada. This report focuses on the demographics, primary diagnoses, clinical indications for transplant, and probability of obtaining liver transplantation for the 1187 children receiving a liver transplant after registration in SPLIT. Demographic information is also provided for the 1092 children who received their first ever liver transplantation. For this cohort, we also describe immunosuppressive practices at the time of transplant, and how the use of different medications changes with time.

Results of 60 consecutive hepatectomies for pediatric living donor liver transplantation

Several technical improvements have been made to increase donor pool for pediatric liver transplantation, including reduced-size grafts, split-liver, and recently living donors. The objective of the present study is to report our single-center experience with 60 hepatectomies for living donor liver transplantation in pediatric recipients between June 2000 and December 2002. Donor workup consisted of a complete history and physical examination followed by laboratory test and liver function tests. Graft size was estimated using computed tomography scan or abdominal ultrasound. Liver biopsy was performed in all donors. Arteriogram was performed to evaluate hepatic arterial anatomy. All donors survived the procedure. Only seven patients experienced complications (10.2%), most of which were short term. We conclude that liver living donation for pediatric population is a safe procedure.

Split liver transplantation

Split liver transplantation offers an attractive way to increase the number of cadaveric grafts. In the past 10 years, it has enabled clinicians to minimise paediatric waiting list mortality. Two major concepts are applied in liver splitting. The more widely accepted approach provides a left lateral and a right extended liver graft to be transplanted into one child and one adult, respectively. To date the results from this technique are comparable to whole organ techniques for both the paediatric and the adult recipient. The second principle of splitting the liver provides two 'full' hemi-grafts-the left side for a small adult or big child and the right for a medium-sized adult patient. Full right/full left splitting is an important means of expanding the adult liver graft pool; however, it is a complex variant of liver transplantation that requires a high level of technical skill and a comprehensive knowledge of possible anatomic variations. Splitting for two adults should be performed in centres with a significant annual volume of liver transplantations, experience with left lateral splitting and an active program of hepatobiliary surgery. This brief review discusses anatomical and technical aspects and summarises the experience of both approaches to split liver transplantation to date.

Current status of liver transplantation in children

There are two critical issues on opposite ends of the timeline for patients who are eligible for liver transplantation. On the one hand, the crisis in the cadaveric organ supply makes surviving to transplant ever more risky. On the other hand, patients who receive successful transplants face the consequences of long-term immunosuppression and its potentially life-threatening complications. The donor shortage is forcing difficult decisions that affect all patients who await liver transplantation. It is important to scrutinize carefully the results of all policies that govern allocation and the ethics of the solutions we advocate to ensure that no patient subgroup is being at a disadvantage. Current immunosuppression practices are being challenged by an increasing understanding of the immunologic events triggered by the allograft and the goal to free patients from consequences of a lifetime of immunosuppression. Clinicians can expect, and perhaps require, that new immunosuppressive protocols will address how the planned intervention might be expected to advance the understanding of tolerance mechanisms. As knowledge increases, clinicians can anticipate innovative new immunosuppressive proposals. Calcineurin and steroid-free induction, the use of donor-derived bone marrow infusion, recipient pretreatment, costimulatory blockade, and new antibody induction approaches are all being proposed--often in combination--for clinical trials. Researchers face additional challenges in defining endpoints if the goal is not just the short-term reduction in rejection but the minimization, and eventual discontinuation, of immunosuppressive drugs while maintaining excellent long-term graft function. How much "failure" will be accepted and how will it be defined? How will clinicians interpret liver biopsies if they begin to accept that some lymphocytic infiltrates may be beneficial mediators of the ongoing immune activation necessary for the maintenance of tolerance? How will they adjust immunosuppression practices to the dynamic processes in the immune response that maintain tolerance? Remarkable short-term successes in providing transplants for thousands of children with liver failure have brought these challenges into sharp focus. Clinicians must seek to move the life-giving science of transplantation toward a new goal: providing long lifetimes of excellent graft function with minimal toxicity from immunosuppressive drugs and the hope of freedom from immunosuppression altogether. Pediatric liver recipients, whose grafts have inherent tolerogenic potential and for whom we can anticipate decades of life after transplant, may prove to be an ideal study population to further these goals.

The process of adult living liver donation

OBJECTIVE

To evaluate both the opinion that living liver donors have of the process and the psychological, economic, and social consequences of donation.

MATERIAL AND METHODS

Six months after the donation, an anonymous survey was sent to 22 donors of the right liver lobe between March 2000 and December 2002.

RESULTS

15 surveys were returned with all of the questions answered. Almost all the donors had no prior knowledge of living donation. When they were considered to be suitable donors, all of them felt happy, 21% were scared and 15% felt joy and insecurity. The information provided was well understood and accurately described the experiences of 93% of donors. All donors understood the vital risk, and 93% understood that transplantation is not always completely successful. All donors would repeat the experience. Mean hospital stay was 12.6 days. Mean convalescence was 50.6 days. Salaried donors were on sick leave for a mean of 96.4 days (21-150 days), causing financial problems in six cases (36%), due to no financial compensation and compulsory redundancy in one case. All donors had completely recovered at six months after donation.

DISCUSSION

Adult living donation of the right liver lobe is an accepted therapeutic alternative. In order to regulate medical and economic protection to avoid additional disturbances after donation, the public, patients, and physicians require more complete information about living donation.

Split-liver transplantation eliminates the need for living-donor liver transplantation in children with end-stage cholestatic liver disease

BACKGROUND

End-stage cholestatic liver disease (ESCLD) is the main indication for liver replacement in children. Pediatric cadaver-organ-donor shortage has prompted the most important evolutions in the technique of liver transplantation, in particular living-donor liver transplantation (LDLT) and split-liver transplantation (SLT).

METHODS

Between November 1997 and June 2001, 127 children with ESCLD were evaluated for liver transplantation, and 124 underwent 138 liver transplantations after a median time of 40 days. Causes of liver disease were congenital biliary atresia (n=96), Alagille's syndrome (n=12), Byler's disease (n=8), and other cholestatic diseases (n=8).

RESULTS

Ninety (73%) patients received a split-liver graft, 28 (23%) a whole liver, and 6 (4%) a reduced-size liver. Overall 2- and 4-year patient survival rates were 93% and 91%, respectively; the 2- and 4-year graft-survival rates were 84% and 80%, respectively. In split-liver recipients, 4-year patient and graft-survival rates were 91% and 83%, respectively; these were 93% and 78%, respectively, in whole-liver recipients and 67% and 63%, respectively, in reduced-size liver recipients. Retransplantation rate was 11%, whereas mortality rate was 8%. Overall incidence of vascular and biliary complication were 16% and 27%, respectively.

CONCLUSIONS

SLT can provide liver grafts for children with ESCLD with an outcome similar to the one reported following LDLT, eliminating mortality while they are on a transplantation wait list. The need for pediatric LDLT should be reevaluated and programs of SLT strongly encouraged and supported at a national and international level.

Blood-transfusion requirements and blood salvage in donors undergoing right hepatectomy for living related liver transplantation

Living related liver donation for liver transplantation in adults including its risks is receiving increased attention. We present data from 44 liver donors focusing on transfusion requirements and avoidance of heterologous transfusion. The volume of blood transfused (both autologous from preoperative donation and heterologous) was assessed including that derived from intraoperative isovolemic hemodilution, cell-saver salvaged, and retransfused blood. Hemoglobin concentration and central venous pressure were measured at specified time points before and during surgery. Intraoperative blood loss was calculated and correlated to the duration of parenchymal transsection, liver volume resected, and central venous pressure. There were no specific anesthesia-evoked complications. In 4 donors, major bleeding (>2000 mL) occurred. Blood loss averaged 902 +/- 564 mL (SD), yielding a minimal mean hemoglobin concentration of 8.1 +/- 1.2 g/dL. One donor received 3 U of heterologous blood and 30 donors received autologous blood from their preoperative donation. An average of 592 +/- 112 mL of blood derived from perioperative acute isovolemic hemodilution was retransfused as was 421 +/- 333 mL of washed red cells from the cell-saving system. Avoidance of heterologous blood transfusion, application of blood-saving techniques, and efficient pain management are crucial for adult living liver donors. Transfusion of banked blood can be avoided in most patients when intraoperative cell salvage, preoperative autologous blood donation, and intraoperative hemodilution are combined.

Recent advances in liver transplantation

Advances in liver transplantation continue to evolve but are hampered by continued increasing shortages in donor organs. This has resulted in a high incidence of patients dying while on the United Network for Organ Sharing waiting list. Indeed, we continue to assess ways of expanding the donor pool by using marginal donors, living donor liver transplantation, split liver transplantation, domino transplantation, and hepatic support systems to prolong survival long enough for the patient to undergo liver transplantation. Changes in the liver allocation policy to reduce the number of people dying while waiting for an organ are discussed. Implementation of the model for end-stage liver disease allocation system should help alleviate the problem of increasing deaths of patients while on the waiting list. Recurrent disease, particularly recurrent hepatitis C, continues to be a major problem, and effective therapy is needed to prevent both progression of hepatitis C and recurrence in the graft and avoid retransplantation. The use of pegylated interferon in combination with ribavirin holds promise for improving the success in overcoming recurrent hepatitis C. Finally, advances in immunosuppression have reduced the incidence of acute cellular rejection and chronic rejection. However, these therapies have been fraught with metabolic complications that are now affecting quality of life and long-term survival. Tailoring immunosuppressive regimens to the individual patient is discussed.

Blood-transfusion requirements and blood salvage in donors undergoing right hepatectomy for living related liver transplantation

Living related liver donation for liver transplantation in adults including its risks is receiving increased attention. We present data from 44 liver donors focusing on transfusion requirements and avoidance of heterologous transfusion. The volume of blood transfused (both autologous from preoperative donation and heterologous) was assessed including that derived from intraoperative isovolemic hemodilution, cell-saver salvaged, and retransfused blood. Hemoglobin concentration and central venous pressure were measured at specified time points before and during surgery. Intraoperative blood loss was calculated and correlated to the duration of parenchymal transsection, liver volume resected, and central venous pressure. There were no specific anesthesia-evoked complications. In 4 donors, major bleeding (>2000 mL) occurred. Blood loss averaged 902 +/- 564 mL (SD), yielding a minimal mean hemoglobin concentration of 8.1 +/- 1.2 g/dL. One donor received 3 U of heterologous blood and 30 donors received autologous blood from their preoperative donation. An average of 592 +/- 112 mL of blood derived from perioperative acute isovolemic hemodilution was retransfused as was 421 +/- 333 mL of washed red cells from the cell-saving system. Avoidance of heterologous blood transfusion, application of blood-saving techniques, and efficient pain management are crucial for adult living liver donors. Transfusion of banked blood can be avoided in most patients when intraoperative cell salvage, preoperative autologous blood donation, and intraoperative hemodilution are combined.

Split liver transplantation and risk to the adult recipient: analysis using matched pairs

BACKGROUND

The technique of liver splitting is an effective way of increasing the donor pool and reducing pediatric waiting list mortality. But the procedure is still not fully accepted because of concerns that it may cause complications in adult recipients.

STUDY DESIGN

Fifty-nine adult recipients of primary extended right split liver transplantations (SLTs) were matched to recipients of whole liver transplantations (WLTs) according to the following criteria: 1) United Network for Organ Sharing (UNOS) status, 2) donor age, 3) recipient age, 4) total cold ischemic time, 5) indication for liver transplantation, 6) Child-Pugh class, and 7) year of transplantation. A WLT-recipient match was identified in 40 adult recipients of primary SLT.

RESULTS

Fifteen percent of the recipients in our study were highly urgent cases (UNOS 1), and 85% were UNOS status 3-4. The 3- and 12-month patient survival rates after SLT and WLT were 82.5% and 77.1%, and 92.5% and 87.5%, respectively (log rank p = 0.358). The 3- and 12-month graft survival rates showed no significant difference in either group (80% and 74% in SLT and 87.5% and 77.4% in WLT [log rank p = 0.887]). The rates of primary nonfunction, primary poor function, biliary and vascular complications, intra- and postoperative blood transfusion, and intensive care stay were comparable for SLT and WLT.

CONCLUSIONS

SLT, using the extended right hepatic lobe, does not notably differ from WLT with regard to initial graft function, postoperative complications, or patient and graft survival. Based on this, the liver can be considered a paired organ, and mandatory splitting of good-quality livers can be recommended.

Donor health assessment after living-donor liver transplantation

OBJECTIVE

To elicit donor opinions on liver living donation through use of a survey that protected the anonymity of the respondent and to assay long-term (follow-up > 1 year) donor health by a widely recognized instrument for health assessment.

SUMMARY BACKGROUND DATA

Living-donor liver transplantation is an accepted technique for children that has recently been extended to adults. Limited donor outcomes data suggest favorable results, but no outcomes data have been reported using an instrument that elicits an anonymous response from the donor or employs a widely recognized health survey.

METHODS

Forty-one living-donors between June 1992 and June 1999 were identified and included in this study, regardless of specific donor or recipient outcome. Each donor received a 68-question survey and a standard McMaster Health Index.

RESULTS

Survey response was 80%. All donors were satisfied with the information provided to them before donation. Eighty-eight percent of donors initially learned of living donation only after their child had been diagnosed with liver disease: 44% through the transplant center, 40% by popular media, 12% by their pediatrician, and 4% by their primary care physician. Physical symptoms, including pain and the surgical wound, were recurrent items of concern. Perception of time to "complete" recovery were less than 3 months (74%), 3 to 6 months (16%), and more than 6 months (10%). Donors' return to physical activities was shown by above-mean McMaster physical scores; scores for social and emotional health were not different from population data. There were no reported changes in sexual function or menstruation after donation, and five of six donors procreated.

CONCLUSIONS

Donors overwhelmingly endorsed living donation regardless of recipient outcome or the occurrence of a complication. Eighty-nine percent advocated "increased" application of living donation beyond "emergency situations," and no donor responded that living donation should be abandoned or that he or she felt "forced" to donate.

Complications following Split-Liver Transplantation: A Pediatric Case Study

Liver transplantation using split and reduced livers has helped to expand the donor pool for pediatric patients in the presence of a severe cadaveric organ donor shortage. However, this technique has been associated with an increased rate of postoperative complications. The purpose of this paper is to review a case report of postoperative complications experienced by a pediatric patient following split-liver transplantation for fulminant hepatic failure of unknown etiology.

Early graft function after pediatric liver transplantation: comparison between in situ split liver grafts and living-related liver grafts

BACKGROUND

The systematic application of living-related and cadaveric, in situ split-liver transplantation has helped to alleviate the critical shortage of suitable-sized, pediatric donors. Undoubtedly, both techniques are beneficial and advantageous; however, the superiority of either graft source has not been demonstrated directly. Because of the potential living-donor risks, we reserve the living donor as the last graft option for pediatric recipients awaiting liver transplantation. Inasmuch as no direct comparison between these two graft types has been performed, we sought to perform a comparative analysis of the functional outcomes of left lateral segmental grafts procured from these donor sources to determine whether differences do exist.

METHODS

A retrospective analysis of all liver transplants performed at a single institution between February 1984 and January 1999 was undertaken. Only pediatric (<18 years) recipients of left lateral segmental grafts procured from either living-related (LRD) or cadaveric, in situ split-liver (SLD) donors were included. A detailed analysis of preoperative, intraoperative, and postoperative variables was undertaken. Survival was estimated using the Kaplan-Meier method, and comparison of variables between groups was undertaken using the t test of Wilcoxon rank sum test.

RESULTS

There were no significant differences in the preoperative variables between the 39 recipients of SLD grafts and 34 recipients of LRD grafts. The donors did differ significantly in mean age, ABO blood group matching, and preoperative liver function testing. Postoperative liver function testing revealed significant early differences in aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, prothrombin time, and alkaline phosphatase, with grafts from LRD performing better than those from SLD. SLD grafts also had significantly longer ischemia times and a higher incidence of graft loss owing to primary nonfunction and technical complications (9 vs. 2, P<0.05). However, six of these graft losses in the SLD group were because of technical or immunologic causes, which, theoretically, should not differ between the two groups. Furthermore, these graft losses did not negatively impact early patient survival as most patients were successfully rescued with retransplantation (30-day actuarial survival, 97.1% SLD vs. 94.1% LRD, P=0.745). In the surviving grafts, the early differences in liver function variables normalized.

CONCLUSIONS

Inherent differences in both donor sources exist and account for differences seen in preoperative and intraoperative variables. Segmental grafts from LRD clearly performed better in the first week after transplantation as demonstrated by lower liver function variables and less graft loss to primary nonfunction. However, the intermediate function (7-30 days) of both grafts did not differ, and the early graft losses did not translate into patient death. Although minimal living-donor morbidity was seen in this series, the use of this donor type still carries a finite risk. We therefore will continue to use SLD as the primary graft source for pediatric patients awaiting liver transplantation.

Is there still a need for living-related liver transplantation in children?

OBJECTIVE

To assess and compare the value of split-liver transplantation (SLT) and living-related liver transplantation (LRT).

SUMMARY BACKGROUND DATA

The concept of SLT results from the development of reduced-size transplantation. A further development of SLT, the in situ split technique, is derived from LRT, which itself marks the optimized outcome in terms of postoperative graft function and survival. The combination of SLT and LRT has abolished deaths on the waiting list, thus raising the question whether living donor liver transplantation is still necessary.

METHODS

Outcomes and postoperative liver function of 43 primary LRT patients were compared with those of 49 primary SLT patients (14 ex situ, 35 in situ) with known graft weight performed between April 1996 and December 2000. Survival rates were analyzed using the Kaplan-Meier method.

RESULTS

After a median follow-up of 35 months, actual patient survival rates were 82% in the SLT group and 88% in the LRT group. Actual graft survival rates were 76% and 81%, respectively. The incidence of primary nonfunction was 12% in the SLT group and 2.3% in the LRT group. Liver function parameters (prothrombin time, factor V, bilirubin clearance) and surgical complication rates did not differ significantly. In the SLT group, mean cold ischemic time was longer than in the LRT group. Serum values of alanine aminotransferase during the first postoperative week were significantly higher in the SLT group. In the LRT group, there were more grafts with signs of fatty degeneration than in the SLT group.

CONCLUSIONS

The short- and long-term outcomes after LRT and SLT did not differ significantly. To avoid the risk for the donor in LRT, SLT represents the first-line therapy in pediatric liver transplantation in countries where cadaveric organs are available. LRT provides a solution for urgent cases in which a cadaveric graft cannot be found in time or if the choice of the optimal time point for transplantation is vital.

Liver transplantation in cystic fibrosis

Liver disease is the second most common cause of death in patients with cystic fibrosis (CF). Improvement in surgical techniques, medical management, and imaging modalities has broadened the range of options for treatment of these patients. Medical management with ursodeoxycholic acid and nutritional support may help decelerate the progression of liver disease. A timely evaluation of CF patients with liver involvement for transplantation is important. Such evaluation should not be delayed until signs of hepatic decompensation occur. Combined lung-liver transplant can be considered for patients with advanced pulmonary disease. Pretransplant management of portal hypertension with a portosystemic shunt procedure is an option for patients with well-preserved synthetic liver function. Improvement in lung function after liver transplantation and no significant risk of pulmonary infection with immunosuppressive therapy have been reported. Review of individual center experiences have shown satisfactory survival and improved quality of life for CF patients undergoing liver transplant.

One hundred nine living donor liver transplants in adults and children: a single-center experience

OBJECTIVE

To summarize the evolution of a living donor liver transplant program and the authors' experience with 109 cases.

SUMMARY BACKGROUND DATA

The authors' institution began to offer living donor liver transplants to children in 1993 and to adults in 1998.

METHODS

Donors were healthy, ages 18 to 60 years, related or unrelated, and ABO-compatible (except in one case). Donor evaluation was thorough. Liver biopsy was performed for abnormal lipid profiles or a history of significant alcohol use, a body mass index more than 28, or suspected steatosis. Imaging studies included angiography, computed tomography, endoscopic retrograde cholangiopancreatography, and magnetic resonance imaging. Recipient evaluation and management were the same as for cadaveric transplant.

RESULTS

After ABO screening, 136 potential donors were evaluated for 113 recipients; 23 donors withdrew for medical or personal reasons. Four donor surgeries were aborted; 109 transplants were performed. Fifty children (18 years or younger) received 47 left lateral segments and 3 left lobes; 59 adults received 50 right lobes and 9 left lobes. The average donor hospital stay was 6 days. Two donors each required one unit of banked blood. Right lobe donors had three bile leaks from the cut surface of the liver; all resolved. Another right lobe donor had prolonged hyperbilirubinemia. Three donors had small bowel obstructions; two required operation. All donors are alive and well. The most common indications for transplant were biliary atresia in children (56%) and hepatitis C in adults (40%); 35.6% of adults had hepatocellular carcinoma. Biliary reconstructions in all children and 44 adults were with a Roux-en-Y hepaticojejunostomy; 15 adults had duct-to-duct anastomoses. The incidence of major vascular complications was 12% in children and 11.8% in adult recipients. Children had three bile leaks (6%) and six (12%) biliary strictures. Adult patients had 14 (23.7%) bile leaks and 4 (6.8%) biliary strictures. Patient and graft survival rates were 87.6% and 81%, respectively, at 1 year and 75.1% and 69.6% at 5 years. In children, patient and graft survival rates were 89.9% and 85.8%, respectively, at 1 year and 80.9% and 78% at 5 years. In adults, patient and graft survival rates were 85.6% and 77%, respectively, at 1 year.

CONCLUSION

Living donor liver transplantation has become an important option for our patients and has dramatically changed our approach to patients with liver failure. The donor surgery is safe and can be done with minimal complications. We expect that living donor liver transplants will represent more than 50% of our transplants within 3 years.

Graft survival in pediatric liver transplantation

BACKGROUND/PURPOSE

Liver transplantation is standard therapy for children with a variety of liver diseases. The current shortage of organ donors has led to aggressive use of reduced or split grafts and living-related donors to provide timely liver transplants to these children. The purpose of this study is to examine the impact of these techniques on graft survival in children currently treated with liver transplantation.

METHODS

Data were obtained on all patients less than 21 years of age treated with isolated liver transplants performed after January 1, 1996 in an integrated statewide pediatric liver transplant program, which encompasses 2 high-volume centers. Nonparametric tests of association and life table analysis were used to analyze these data (SAS v 6.12).

RESULTS

One hundred twenty-three children received 147 grafts (62 at the University of Florida, 85 at the University of Miami). Fifty-two (36%) children were less than 1 year of age at time of transplant, and 80 (55%) were less than 2 years of age. Patient survival rate was identical in the 2 centers (1-year actuarial survival rate, 88.4% and 87.1%). Twenty-five (17%) grafts were reduced, 28 (19%) were split, 6 were from living donors (4%), and 88 (60%) were whole organs. One-year graft survival rate was 80% for whole grafts, 71.6% for reduced grafts, and 64.3% for split grafts (P =.06). Children who received whole organs (mean age, 6.1 years) were older than those who received segmental grafts (mean age, 2.5 years; P <.01). Multifactorial analysis suggested that patient age, gender, and use of the graft for retransplant did not influence graft survival, nor did the type of graft used influence patient survival.

CONCLUSIONS

The survival rate of children after liver transplantation is excellent independent of graft type. Use of current techniques to split grafts between 2 recipients is associated with an increased graft loss and need for retransplantation. Improvement in graft survival of these organs could reduce the morbidity and cost of liver transplantation significantly in children.

Liver transplantation

Continued discussion over organ allocation and distribution remained a focal point in the field of liver transplantation in the year 2000. Despite the ongoing debate, no significant changes were implemented in the current allocation system. By far, the most widely discussed topic in liver transplantation this year was live donor adult-to-adult liver transplantation. Several authors reported on their initial experience, with both recipient and donor outcomes appearing excellent. As the number of transplant centers performing this procedure increases we look forward to further studies regarding the safety and long-term outcome of this innovative procedure. Studies on viral hepatitis after liver transplantation again focused on the problem of recurrent hepatitis B and hepatitis C. Several small studies found benefit in patients with hepatitis B treated with intramuscular hepatitis B immunoglobulin and lamivudine after transplantation. Although breakthrough replication remains a problem in some patients, these studies offer hope that combination therapy for hepatitis B may provide improved long-term graft survival in these patients. In patients with hepatitis C, several studies focused on identifying risk factors to predict graft recurrence of the virus after liver transplantation. Both cellular rejection and level of viral replication may be important predictors of recurrent hepatitis C virus in the graft. Early treatment reports using interferon and ribavirin suggest that some patients may have a viral response during therapy; however, it is short lived, and tolerance of medication is difficult. Certainly, we look forward to further studies looking at means of prevention and treatment of viral hepatitis in patients undergoing liver transplantation.