How can we define expanded criteria for liver donors?

Increasing liver transplantation waiting list mortality: a report from the Australian National Liver Transplantation Unit, Sydney

BACKGROUND

We aimed to describe the demand for liver transplantation (LTx) and patient outcomes on the waiting list at the Australian National Liver Transplantation Unit, Sydney over the last 20 years.

METHODS

We performed a retrospective analysis with the data divided into three eras: 1985-1993, 1994-2000 and 2001-2008.

RESULTS

The number of patients accepted for LTx increased from 320 to 372 and 548 (P < 0.001) with the number of LTx being performed increasing from 262 to 312 and 452 respectively (P < 0.001). The median adult recipient age increased from 45 to 48 and 52 years (P < 0.001) while it decreased in children from 4 to 2 and 1 years respectively (P = 0.001). In parallel, the deceased donor offers decreased from 1003 to 720 and 717 (P < 0.001). Methods to improve access to donor livers have been used with the use of split livers, extended criteria and non-heart beating donors, resulting in increased acceptance of deceased donor offers by 65% and 115% in the second and third eras when compared with the first era (P < 0.001). However, the adult median waiting time has increased from 23 to 41 and 120 days respectively (P < 0.001). This was associated with increased adult mortality on the waiting list from 23 to 40 and 122 respectively (P < 0.001).

CONCLUSIONS

Despite the increasing proportion of donor offers being used, the waiting list mortality is increasing. A solution to this problem is an increase in organ donation to keep pace with the escalating demand for LTx.

Domino versus deceased donor liver transplantation: association with early graft function and perioperative bleeding

This study sought to evaluate the potential impact of domino liver transplantation (DLT) on initial graft function and early postoperative outcome in patients with cirrhosis in a Portuguese liver transplantation center. A retrospective comparative analysis was performed between 77 domino recipients (from familial amyloidotic polyneuropathy donors) and 91 deceased donor recipients, all submitted to primary elective whole liver transplantation, using the piggyback technique, in a 42-month period. Outcome parameters included graft dysfunction (defined as either primary nonfunction or initial poor function, according to the Ploeg-Maring criteria) and Clavien II-IV complications in the first postoperative week. Domino and deceased donor recipients had similar preoperative severity indices (Child-Pugh classification and Model for End-Stage Liver Disease score) and immediate postoperative severity scores (APACHE II [Acute Physiology and Chronic Health Evaluation II] and SAPS II [Simplified Acute Physiology Score II]). In DLT, donors were younger, cold ischemia time was shorter, and intraoperative transfusion requirements of packed red blood cells and fresh-frozen plasma were significantly lower. Graft dysfunction incidence was 3.4-fold lower in DLT: 5.2% (only 4 cases of initial poor function) versus 18.0% (1 primary nonfunction and 15 cases of initial poor function), P = 0.010. Postoperative bleeding was the most frequent early Clavien II-IV complication (n = 29, 17.3%), with an incidence 2.2-fold lower in domino recipients. A statistically significant difference was not found in the other analyzed Clavien II-IV complications, intensive care unit stay, mechanical ventilation time, intensive care unit mortality, and 1-year survival rate. In conclusion, in this study the younger donors and shorter ischemic time associated with DLT may provide a protective role in regards to graft dysfunction and perioperative bleeding, which are 2 important determinants of early morbidity after liver transplantation.

The interaction among donor characteristics, severity of liver disease, and the cost of liver transplantation

Accurate assessment of the impact of donor quality on liver transplant (LT) costs has been limited by the lack of a large, multicenter study of detailed clinical and economic data. A novel, retrospective database linking information from the University HealthSystem Consortium and the Organ Procurement and Transplantation Network registry was analyzed using multivariate regression to determine the relationship between donor quality (assessed through the Donor Risk Index [DRI]), recipient illness severity, and total inpatient costs (transplant and all readmissions) for 1 year following LT. Cost data were available for 9059 LT recipients. Increasing MELD score, higher DRI, simultaneous liver-kidney transplant, female sex, and prior liver transplant were associated with increasing cost of LT (P < 0.05). MELD and DRI interact to synergistically increase the cost of LT (P < 0.05). Donors in the highest DRI quartile added close to $12,000 to the cost of transplantation and nearly $22,000 to posttransplant costs in comparison to the lowest risk donors. Among the individual components of the DRI, donation after cardiac death (increased costs by $20,769 versus brain dead donors) had the greatest impact on transplant costs. Overall, 1-year costs were increased in older donors, minority donors, nationally shared organs, and those with cold ischemic times of 7-13 hours (P < 0.05 for all). In conclusion, donor quality, as measured by the DRI, is an independent predictor of LT costs in the perioperative and postoperative periods. Centers in highly competitive regions that perform transplantation on higher MELD patients with high DRI livers may be particularly affected by the synergistic impact of these factors.

Liver Match, a prospective observational cohort study on liver transplantation in Italy: study design and current practice of donor-recipient matching

BACKGROUND

The Liver Match is an observational cohort study that prospectively enrolled liver transplantations performed at 20 out of 21 Italian Transplant Centres between June 2007 and May 2009. Aim of the study is to investigate the impact of donor/recipient matching on outcomes. In this report we describe the study methodology and provide a cross-sectional description of donor and recipient characteristics and of graft allocation.

METHODS

Adult primary transplants performed with deceased heart-beating donors were included. Relevant information on donors and recipients, organ procurement and allocation were prospectively entered in an ad hoc database within the National Transplant Centre web-based Network. Data were blindly analysed by an independent Biostatistical Board.

RESULTS

The study enrolled 1530 donor/recipient matches. Median donor age was 56 years. Female donors (n = 681, median 58, range 12-92 years) were older than males (n = 849, median 53, range 2-97 years, p < 0.0001). Donors older than 60 years were 42.2%, including 4.2% octogenarians. Brain death was due to non-traumatic causes in 1126 (73.6%) cases. Half of the donor population was overweight, 10.1% was obese and 7.6% diabetic. Hepatitis B core antibody (HBcAb) was present in 245 (16.0%) donors. The median Donor Risk Index (DRI) was 1.57 (>1.7 in 35.8%). The median cold ischaemia time was 7.3h (≥ 10 in 10.6%). Median age of recipients was 54 years, and 77.7% were males. Hepatocellular carcinoma (HCC) was the most frequent indication overall (44.4%), being a coindication in roughly 1/3 of cases, followed by viral cirrhosis without HCC (28.2%) and alcoholic cirrhosis without HCC (10.2%). Hepatitis C virus infection (with or without HCC) was the most frequent etiologic factor (45.9% of the whole population and 71.4% of viral-related cirrhosis), yet hepatitis B virus infection accounted for 28.6% of viral-related cirrhosis, and HBcAb positivity was found in 49.7% of recipients. The median Model for End Stage Liver Disease (MELD) at transplant was 12 in patients with HCC and 18 in those without. Multivariate analysis showed a slight but significant inverse association between DRI and MELD at transplant.

CONCLUSIONS

The deceased donor population in Italy has a high-risk profile compared to other countries, mainly due to older donor age. Almost half of the grafts are transplanted in recipients with HCC. Higher risk donors tend to be preferentially allocated to recipients with HCC, who are usually less ill and older. No other relevant allocation strategy is currently adopted at national level.

Prediction of graft dysfunction based on extended criteria donors in the model for end-stage liver disease score era

BACKGROUND

To explain the influence of recipient status combined with the accumulation of extended criteria donor (ECD) variables on the appearance of severe ischemia-reperfusion injury and graft survival in a model for end-stage liver disease (MELD)-based system, we analyzed our most recent consecutive liver transplantations (LTs), dividing them into two periods: 400 LTs (1992-2002; pre-MELD era) and 275 LTs (2002-2007; post-MELD era).

METHODS

Primary dysfunction (PD) was defined as primary graft failure that required emergency retransplantation or as initial poor function. Donor variables were included in a regression model to assess the probability of PD.

RESULTS

Donor age, macrovesicular steatosis more than 30%, and cold ischemia time were associated with allograft dysfunction. Mean probability of PD was 14.8%, 19.2%, 27.5%, and 37.4% for ECD 0, 1, 2, and more than or equal to 3, respectively (P=0.003). Distribution of no-mild, moderate, and severe ischemia-reperfusion injuries among MELD categories was 72.53%, 24.17%, and 3.30% (MELD group=12-19); 56.52%, 36.96%, and 6.5% (MELD group=20-28); and 23.91%, 54.35%, and 21.74% (MELD group >or=29), respectively (P=0.043). The development of PD according to ECD variables was 18.8%, 18.1%, 28.0%, and 35.3% for ECD 0, 1, 2, and more than or equal to 3, respectively (P=0.047). These variables were independent predictors of PD (Cox proportional regression model): ECD 2 (relative risk [RR]=1.59; 95% confidence interval [CI]=1.25-1.62), ECD 3 (RR=2.74; 95% CI=2.38-3.13), MELD 21 to 30 (RR=1.89; 95% CI=1.32-2.06), and MELD more than or equal to 30 (RR=3.38; 95% CI=2.43-3.86). Graft survival decreased, whereas MELD and the number of ECD variables increased.

CONCLUSION

The combination of three or more ECD variables and an MELD more than or equal to 29 is the worst scenario for graft success after LT.

Validation of a current definition of early allograft dysfunction in liver transplant recipients and analysis of risk factors

Translational studies in liver transplantation often require an endpoint of graft function or dysfunction beyond graft loss. Prior definitions of early allograft dysfunction (EAD) vary, and none have been validated in a large multicenter population in the Model for End-Stage Liver Disease (MELD) era. We examined an updated definition of EAD to validate previously used criteria, and correlated this definition with graft and patient outcome. We performed a cohort study of 300 deceased donor liver transplants at 3 U.S. programs. EAD was defined as the presence of one or more of the following previously defined postoperative laboratory analyses reflective of liver injury and function: bilirubin >or=10mg/dL on day 7, international normalized ratio >or=1.6 on day 7, and alanine or aspartate aminotransferases >2000 IU/L within the first 7 days. To assess predictive validity, the EAD definition was tested for association with graft and patient survival. Risk factors for EAD were assessed using multivariable logistic regression. Overall incidence of EAD was 23.2%. Most grafts met the definition with increased bilirubin at day 7 or high levels of aminotransferases. Of recipients meeting the EAD definition, 18.8% died, as opposed to 1.8% of recipients without EAD (relative risk = 10.7 [95% confidence interval: 3.6, 31.9] P < 0.0001). More recipients with EAD lost their grafts (26.1%) than recipients with no EAD (3.5%) (relative risk = 7.4 [95% confidence interval: 3.4, 16.3] P < 0.0001). Donor age and MELD score were significant EAD risk factors in a multivariate model. In summary a simple definition of EAD using objective posttransplant criteria identified a 23% incidence, and was highly associated with graft loss and patient mortality, validating previously published criteria. This definition can be used as an endpoint in translational studies aiming to identify mechanistic pathways leading to a subgroup of liver grafts with clinical expression of suboptimal function.

Biological modulation of liver ischemia-reperfusion injury

PURPOSE OF REVIEW

This review gives a broad overview of the key factors of ischemic injury to the liver and presents the current modifications of preservation solutions and the few strategies of biological modulation in clinical use today.

RECENT FINDINGS

Protective effects in human-liver transplantation were shown by methylprednisolone treatment in decreased donors, and by inhalation of a nontoxic dose of nitric oxide in recipients. In addition, recent results showed rescue of pig livers, donated after cardiac death by application of a cocktail of substances addressing several previously identified mechanisms of ischemia-reperfusion injury.

SUMMARY

The future of a pharmacological approach attenuating or preventing ischemia-reperfusion injury lies in a combination of drugs acting simultaneously on several steps of the injury cascades. Applying these substances during flush, before, and during implantation appears as an attractive strategy to protect extended criteria liver grafts.

Model of end stage liver disease (MELD) score greater than 23 predicts length of stay in the ICU but not mortality in liver transplant recipients

Introduction

The impact of model of end stage liver disease (MELD) score on postoperative morbidity and mortality is still elusive, especially for high MELD. There are reports of poorer patient outcome in transplant candidates with high MELD score, others though report no influence of MELD score on outcome and survival.

Methods

We retrospectively analyzed data of 144 consecutive liver transplant recipients over a 72-month period in our transplant unit, from January 2003 until December 2008 and performed uni- and multivariate analysis for morbidity and mortality, in particular to define the influence of MELD to these parameters.

Results

This study identified MELD score greater than 23 as an independent risk factor of morbidity represented by intensive care unit (ICU) stay longer than 10 days (odds ratio 7.0) but in contrast had no negative impact on mortality. Furthermore, we identified transfusion of more than 7 units of red blood cells as independent risk factor for mortality (hazard ratio 7.6) and for prolonged ICU stay (odds ratio [OR] 7.8) together with transfusion of more than 10 units of fresh frozen plasma (OR 11.6). Postoperative renal failure is a strong predictor of morbidity (OR 7.9) and postoperative renal replacement therapy was highly associated with increased mortality (hazard ratio 6.8), as was hepato renal syndrome prior to transplantation (hazard ratio 13.2).

Conclusions

This study identified MELD score greater than 23 as an independent risk factor of morbidity represented by ICU stay longer than 10 days but in contrast had no negative impact on mortality. This finding supports the transplantation of patients with high MELD score but only with knowledge of increased morbidity.

One hour hypothermic oxygenated perfusion (HOPE) protects nonviable liver allografts donated after cardiac death

OBJECTIVES

To test, in a large animal model, the efficacy of machine perfusion to rescue livers after prolonged ischemic injury.

BACKGROUND

Our group previously showed in various rodent models the benefit of endischemic hypothermic oxygenated perfusion (HOPE) in protecting liver injury from donation after cardiac death (DCD). Convincing results are needed in large animal models before application in human.

METHODS

A new model of DCD liver transplantation in large pigs was developed. Pig livers (1300 +/- 210 g each) were harvested 60 minutes after induction of cardiac death (respirator withdrawal). In situ flush and organ procurement were initiated without heparin pretreatment. Then, livers were preserved for 7 hours in cold Celsior (DCD-group) prior to orthotopic transplantation (OLT). Some livers were treated by 1 hour HOPE prior to implantation (HOPE-group). In a first step, animals were kept under anesthesia for 6 hours after orthotopic transplantation. Endpoints included serum (AST) and tissue (ATP, glutathione) markers of injury, bile flow, and histology. In a second step, survival experiments were performed.

RESULTS

Livers from the DCD group displayed diffuse necrosis of hepatocytes, increased adhesion of platelets, high AST release, absence of bile flow, depletion of glutathione, and ATP. In contrast, livers treated with HOPE showed dramatic reduction of necrosis, platelet adhesion, while bile flow, ATP recovery and glutathione were improved. Importantly, untreated DCD livers caused graft failure and death of all recipients within 6 hours of reperfusion, whereas HOPE treated DCD livers remained hemodynamically stable.

CONCLUSIONS

This is the first study in a reliable large animal transplant model demonstrating the efficacy of a simple cold oxygenated machine perfusion system to rescue, otherwise lethal, ischemic injured DCD liver grafts.

Liver transplantations with donors aged 60 years and above: the low liver damage strategy

According to transplant registries, grafts from elderly donors have lower survival rates. During 1999-2005, we evaluated the outcomes of 89 patients who received a liver from a donor aged > or = 60 years and managed with the low liver-damage strategy (LLDS), based on the preoperative donor liver biopsy and the shortest possible ischemia time (group D > or = 60-LLDS). Group D > or = 60-LLDS was compared with 198 matched recipients, whose grafts were not managed with this strategy (89 donors < 60 years, group D < 60-no-LLDS and 89 donors aged > or =60 years, group D > or = 60-no-LLDS). In the donors proposed from the age group of > or =60 years, the number of donors rejected decreased during the study period and the LLDS was found to be responsible for this in a significant manner (47% vs. 60%, respectively P < 0.01). Among the recipients transplanted, the clinical features (age, gender, viral infection, child and model for end-stage liver disease score) were comparable among groups, but group D > or = 60-LLDS had a lower mean ischemia time: 415 +/- 106 min vs. 465 +/- 111 (D < 60-no-LLDS), P < 0.05 and vs. 476 +/- 94 (D > or = 60-no-LLDS), P < 0.05. After a median follow-up of 3 years, the 1- and 3-year graft survival rates of group D > or = 60-LLDS (84% and 76%) were comparable with group D < 60-no-LLDS (89% and 76%) and were significantly higher than group D > or = 60-no-LLDS (71% and 54%), P < 0.005. In conclusion, the LLDS optimized the use of livers from elderly donors.

Abdominal drains in liver transplantation: useful tool or useless dogma? A matched case-control study

On the basis of the growing evidence from randomized trials that routine prophylactic drainage is unnecessary in liver surgery or even harmful in chronic liver disease, we challenged the concept of prophylactic drainage in orthotopic liver transplantation (OLT). Since September 2006, we omitted drains in every patient who underwent OLT, regardless of the procedure. Thirty-five cadaveric OLTs were performed during a 12-month period. These patients were matched 1:2 with 70 patients who had prophylactic drainage after OLT according to donor/recipient age, recipient gender, recipient body mass index, and Model for End-Stage Liver Disease (MELD) score. Endpoints were postoperative morbidity, in-hospital mortality, intensive care unit (ICU), and hospital stay. Complications were graded according to a therapy-oriented classification (grades I-V). Both groups (no drainage, n = 35; drainage, n = 70) were comparable in terms of median donor age (47.5 versus 51.0 years), recipient age (50.6 versus 52.0 years), MELD score (18 versus 14), and body mass index (25.3 versus 26 kg/m(2)). Because of the increasing shortage of organs, more marginal grafts were used in the recent period (ie, no-drainage group): 49% (17/35) versus 27% (19/70; P = 0.04). Major complications were not different between groups: grade 3a (endoscopic/radiological intervention) in 20% (7/35) versus 16% (11/70; not significant), grade 3b (surgical intervention) in 23% (8/35) versus 17% (12/70; not significant), grade 4a (ICU therapy, intermittent hemodialysis) in 34% (12/35) versus 21% (15/70; not significant), grade 4b (multiorgan failure) in 14% (5/35) versus 10% (7/70; not significant), and grade 5 (death) in 6% (2/35) versus 7% (5/70; not significant). This matched case study challenges the dogma of prophylactic drainage after OLT. A no-drain strategy provided no disadvantages despite increased use of extended criteria donors in the no-drainage group. Prophylactic drainage appears unnecessary on a routine basis.

Donor age and cold ischemia interact to produce inferior 90-day liver allograft survival

BACKGROUND

Expanded regional sharing of liver allografts may increase cold ischemia and allograft failure, particularly with livers from older donors. The aim of this study was to examine whether older donor age and cold ischemic time interact to produce inferior allograft survival.

METHODS

We undertook a retrospective cohort study of adult liver transplants in the United States performed between December 1, 1995 and December 31, 2005, using data from the Organ Procurement and Transplantation Network. The primary outcome was allograft failure within 90 days.

RESULTS

Forty-four thousand seven hundred fifty-six liver transplant recipients were analyzed. Older age was defined as 45 years or more, and prolonged cold ischemia was defined as 12 hours or more. Using data from the pre-Model for End Stage Liver Disease (MELD), post-MELD and combined eras, three separate analyses of the interaction between older donor age and prolonged cold ischemia were performed. In multivariable logistic regression, the interaction of age 45 years or more and cold ischemia more than or equal to 12 hr reached statistical significance in the combined (OR 1.24, CI 1.08-1.42, P<0.01) and pre-MELD (OR 1.26, CI 1.08-1.46, P<0.01) datasets, but not in the smaller post-MELD dataset (OR 1.18, CI 0.81-1.72, P=0.38). In the combined dataset, recipients of livers from donors aged 45 years or more and cold ischemia more than or equal to 12 hr showed an adjusted absolute risk of allograft failure at 90 days of 17.3% (odds ratio 1.84), compared with 11.1% for recipients of livers from donors older than 45 years and cold ischemia less than 12 hr.

CONCLUSIONS

These findings suggest that older donor age and prolonged cold ischemia interact to increase liver allograft failure at 90 days. Proposals to expand regional sharing of older livers should be regarded with caution.

Impact of cumulative risk factors for expanded criteria donors on early survival after liver transplantation

There are various options to help overcome the organ shortage, including performing transplants using grafts from marginal donors with characteristics previously described as unacceptable because of the high risk of graft failure. Nowadays, expanded criteria donors for liver transplantation (OLT) is a strategy used routinely by many teams. Some donor features have been suggested to jeopardize initial function or survival; when these features are aggregated, they may impact prognosis. The aim of this study was to evaluate the impact of donor risk factors on early patient survival and retransplantation. Donor risk factors were considered to be older than 60 years, body mass index > 30, serum sodium level > 155 mEq/L, cold ischemia time > 12 hours, and intensive care unit stay > 4 days. We prospectively recorded data from 139 patients who underwent 152 OLT from March 2003 to May 2007. Patients were classified into four groups: I, no risk factors; II, one risk factor; III, two risk factors; IV, three or more risk factors. Retransplantation or OLT due to acute liver failure was considered to be an exclusion criterion. Early overall survival rate was 83.76%; 12 retransplantations were required (10.25%). Comparing the four groups, patient survivals (P = .41) and retransplantation rates (P = .518) were similar. In conclusion, cumulative risk factors showed no impact on early (30-day) recipient survival and or on the necessity of retransplantation after OLT.

Hot topics in liver transplantation: organ allocation--extended criteria donor--living donor liver transplantation

Liver transplantation has become the mainstay for the treatment of end-stage liver disease, hepatocellular cancer and some metabolic disorders. Its main drawback, though, is the disparity between the number of donors and the patients needing a liver graft. In this review we will discuss the recent changes regarding organ allocation, extended donor criteria, living donor liver transplantation and potential room for improvement. The gap between the number of donors and patients needing a liver graft forced the transplant community to introduce an objective model such as the modified model for end-stage liver disease (MELD) in order to obtain a transparent and fair organ allocation system. The use of extended criteria donor livers such as organs from older donors or steatotic grafts is one possibility to reduce the gap between patients on the waiting list and available donors. Finally, living donor liver transplantation has become a standard procedure in specialized centers as another possibility to reduce the donor shortage. Recent data clearly indicate that center experience is of major importance in achieving good results. Great progress has been made in recent years. However, further research is needed to improve results in the future.

Controversies in liver transplantation for hepatitis C

Hepatitis C is one of the most common indications for liver transplantation in the United States, accounting for approximately 40%-45% of all liver transplants. Unfortunately, recurrent disease is universal in patients who are viremic before transplantation. This can lead to cirrhosis in at least 25% of patients 5 years after liver transplantation, and recurrent hepatitis C is now emerging as an important but occasionally contentious indication for retransplantation. Several attempts have been undertaken to identify patients at high risk for severe recurrent disease who may benefit from treatment, but unfortunately antiviral therapy frequently is ineffective and often is associated with numerous side effects. Although we have made significant strides in understanding the natural history of this disease in nontransplant patients, this does not hold true for the transplant population in which several uncertainties covering virtually the entire spectrum of liver transplantation persist. Despite these concerns, on a more practical level, it is usually only in the postoperative setting that clinicians truly can assess the impact of their interventions on the natural history of recurrent hepatitis C, for example, by adjusting immunosuppression or prescribing antiviral therapy. Preoperative and perioperative (including donor) factors often are outside the control of hepatologists and transplant surgeons. This review is not an inclusive review of the literature but summarizes what we believe are the more controversial topics of this disease.

Machine perfusion for 'marginal' liver grafts

Due to the critical shortage of deceased donor grafts, clinicians are continually expanding the criteria for an acceptable liver donor to meet the waiting list demands. However, the reduced ischemic tolerance of those extended criteria grafts jeopardizes organ viability during cold storage. Machine perfusion has been developed to limit ischemic liver damage but despite its proven biochemical benefit, machine liver perfusion is not yet considered clinically due to its low practicability. In this review, we summarize our understanding of the role of machine perfusion in marginal liver preservation. The goal is to highlight advantages or disadvantages of current perfusion techniques and to explain the underlying mechanisms. We provide evidence for the need of a liver perfusion performance shortly before implantation, and point out promising designs.

Comparison of histidine-tryptophan-ketoglutarate solution and University of Wisconsin solution in extended criteria liver donors

Liver, pancreas, and kidney allografts preserved in histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) solutions have similar clinical outcomes. This study compares HTK and UW in a large number of standard criteria donor (SCD) and extended criteria donor (ECD) livers at a single center over 5 years. All adult, cadaveric liver and liver-kidney transplants performed between July 1, 2001 and June 30, 2006 were reviewed (n = 698). There were 435 livers (62%) categorized as ECD for severe physiologic stress and 70 (10%) because of old age. Recipient outcomes included perioperative death or graft loss and overall survival. Liver enzymes were analyzed for the first month post-transplant. Biliary complications were assessed through chart review. Overall, 371 donor livers were preserved in HTK (53%), and 327 were preserved in UW (47%). There were no statistically significant differences in any of the primary outcome measures comparing HTK and UW. The HTK group overall had a higher day 1 median aspartate aminotransferase and alanine aminotransferase, but the two groups were similar in function thereafter. HTK was superior to UW in protection against biliary complications. Kaplan-Meier graft survival curves failed to demonstrate a significant difference in SCD or ECD livers. In conclusion, HTK and UW are not clinically distinguishable in this large sample of liver transplants, although HTK may be protective against biliary complications when compared to UW. These findings persisted for both SCD and ECD livers. Given the lower cost per donor for HTK, this preservation solution may be preferable for general use.

Use of severely steatotic grafts in liver transplantation: a matched case-control study

BACKGROUND

Although there is a worldwide need to expand the pool of available liver grafts, cadaveric livers with severe steatosis (>60%) are discarded for orthotopic liver transplantation (OLT) by most centers.

METHODS

We analyzed patients receiving liver grafts with severe steatosis between January 2002 and September 2006. These patients were matched 1:2 with control patients without severe steatosis according to status the waiting list, recipient age, recipient body mass index (BMI), and model for end-stage liver disease (MELD) score. Primary end points were the incidence of primary graft nonfunction (PNF), and graft and patient survival. Secondary end points included primary graft dysfunction (PDF), the incidence of postoperative complications, and histologic assessment of steatosis in follow-up biopsies. We also conducted a survey on the use of grafts with severe steatosis among leading European liver transplant centers.

RESULTS

During the study period, 62 patients dropped out of the waiting list and 45 of them died due to progression of disease. Of 118 patients who received transplants 20 (17%) received a graft with severe steatosis during this period. The median degree of total liver steatosis was 90% (R = 65%-100%) for the steatotic group. The steatotic (n = 20) and matched control group (n = 40) were comparable in terms of recipient age, BMI, MELD score, and cold ischemia time. The steatotic group had a significantly higher rate of PDF and/or renal failure. Although the median intensive care unit (ICU) and hospital stay were not significantly different between both groups, the proportion of patients with long-term ICU (> or =21 days) and hospital (> or =40 days) stay was significantly higher for patients with a severely steatotic graft. Sixty-day mortality (5% vs. 5%) and 3-year patient survival rate (83% vs. 84%) were comparable between the control and severe steatosis group. Postoperative histologic assessment demonstrated that the median total amount of liver steatosis decreased significantly (median: 90% to 15%, P < 0.001). Our survey showed that all but one of the European centers currently reject liver grafts with severe steatosis for any recipient.

CONCLUSION

Due to the urgent need of liver grafts, severely steatotic grafts should be no longer discarded for OLT. Maximal effort must be spent when dealing with these high-risk organs but the use of severely steatotic grafts may save the lives of many patients who would die on the waiting list.