Transplantation einer Spenderleber auf zwei Empf�nger (Splitting-Transplantation) - Eine neue Methode in der Weiterentwicklung der Lebersegmenttransplantation

In situ splitting of the cadaveric liver for transplantation

BACKGROUND

The shortage of cadaveric donor livers is the rate-limiting step in clinical liver transplantation. Split liver transplantation provides a means to expand the cadaveric donor pool. However, this concept has not reached its full potential because of inferior patient and graft survival and high complication rates when traditional ex vivo split techniques are used. Therefore we sought to evaluate the safety, applicability, and effectiveness of a new technique for split liver transplantation.

METHODS

This study consists of 15 in situ split liver procurements, which resulted in 28 liver transplants. In situ splitting of selected livers from hemodynamically stable cadaveric donors was performed at the donor hospital without any additional work-up or equipment being needed. In situ liver splitting is accomplished in a manner identical to the living-donor procurement. This technique for liver splitting results in a left lateral segment graft (segments 2 and 3) and a right trisegmental graft (segments 1 and 4-8). This procedure required the use of the donor hospital operating room for an additional 1.5-2.5 hr and did not interfere with the procurement of 30 kidneys, 12 hearts, 7 lungs, and 9 pancreata from these same donors.

RESULTS

The 6-month and 1-year actuarial patient survival rates were 92% and 92%, respectively, while the 6-month and 1-year actuarial graft survival rates were 86% and 86%, respectively. The 6-month and 1-year actuarial patient survival rate of patients who received a left lateral segment graft was 100% and 100%, respectively, while those who received a right trisegmental graft had 6-month and 1-year rates of 86% and 86%, respectively. The actuarial death-censored graft survival rates at 6 months and 1 year were 80% and 80%, respectively, for the left lateral segment grafts, and 93% and 93%, respectively, for the right trisegmental grafts. Alograft and patient survival was independent of United Network for Organ Sharing status at the time of liver transplantation. No patient developed a biliary stricture, required re-exploration for intra-abdominal hemorrhage, or suffered from portal vein, hepatic vein, or hepatic artery thrombosis

CONCLUSIONS

In situ split liver transplantation can be accomplished without complications and provides results that are superior to those obtained previously with ex vivo methods. It abolishes ex vivo benching and prolonged ischemia times and provides two optimal grafts with hemostasis accomplished. This technique decreases pediatric waiting time and allows adult recipients to receive right-sided grafts safely. In situ splitting is the method of choice for expanding the cadaveric liver donor pool.

Progress in pediatric liver transplantation--the Birmingham experience

This report describes the evolution of the Birmingham, UK experience with pediatric liver transplantation from 1983 to present. Two hundred liver grafts were placed in 168 children less than 17 years of age. The current survival rate exceeds 80%.

Attenuation of ischemic liver injury by augmentation of endogenous adenosine

Hepatic grafts from non-heartbeating donors may alleviate the organ shortage, but they inherently suffer from warm ischemia. In the present study, we tested our hypothesis that augmentation of endogenous adenosine by inhibition of nucleoside transport with R75231 attenuates ischemic liver injury. Adult female beagle dogs underwent 2-hr hepatic vascular exclusion with venovenous bypass. R75231 was given to the animals by continuous intravenous infusion for 30 min before ischemia at a dose of 0.1 mg/kg (Group 2, n=6), 0.05 mg/kg (Group 3, n=6), or 0.025 mg/kg (Group 4, n=6). Nontreated animals were used as the control (Group 1, n= 10). Animal survival, hepatic tissue blood flow, liver function, and histopathology were analyzed. Two-week animal survival was 30% in Group 1, 83% in Group 2, 100% in Group 3, and 100% in Group 4. Postreperfusion hepatic tissue blood flow was markedly improved by the treatment. Treatment significantly attenuated liver enzyme release, lipid peroxidation, and changes in adenine nucleotides and purine catabolites. Structural abnormality of the liver after reperfusion was markedly improved by R75231 treatment, showing better architecture and less neutrophil infiltration. Preischemic administration of a nucleoside transport inhibitor ameliorated ischemic liver injury due to the positive effects of augmented endogenous adenosine, and is applicable clinically when the liver is procured from a controlled non-heartbeating donor.

Function of reduced-size liver transplant in the rat

We have studied the function of partial orthotopic liver transplantation in the rat by evaluating prothrombin time (PT), liver blood flow, basal and glucose-stimulated insulin secretion and glucose tolerance, and the reticuloendothelial function (RES) in hepatectomized rats subjected to partial liver transplantation. A graft corresponding to 68% of a normal liver was transplanted to totally hepatectomized rats. Comparison was made between control rats and rats subjected to 32% liver resection. PT was not significantly different in the transplanted group compared with liver-resected and control rats. Laser Doppler flowmetry showed that at 28 days after surgery, blood flow had increased in the transplanted livers. Furthermore, on the third day after transplantation, basal plasma insulin was increased and the plasma insulin response to glucose was exaggerated, suggesting reduced insulin action and impaired insulin degradation. Finally, uptake of radioactive-labeled E. coli bacteria, as a measure of RES function, was not compromised in transplanted animals. Based on these results, we conclude that reduced-size liver transplant in out-bred rats results in fast normalization of liver function after surgery although, immediately after surgery, glucose intolerance is seen.

Split-liver transplantation. The Paul Brousse policy

OBJECTIVE

The authors objective is to report their recent experience with split-liver transplantation, focusing on the results and the impact on organ shortage.

SUMMARY BACKGROUND DATA

There is an insufficient number of organs for liver transplantation. Split-liver transplantation is a method to increase the number of grafts, but the procedure is slow to gain wide acceptance because of its complexity and the poor results reported in previous series.

METHODS

During the year 1995, the authors split 20 of 83 transplantable livers allocated to the authors' center, generating 40 grafts: 23 were transplanted locally and 17 were given to partner centers. During the same period, the authors accepted four split-liver grafts proposed to them by other centers. Overall, 27 split-liver transplantations were done in the authors' unit, accounting for 30% of the 90 transplants performed in 1995.

RESULTS

One-year patient and graft survival rates for split-liver transplantation were 79.4% and 78.5%, respectively. Arterial and biliary complications rates were 15% and 22%, respectively, with none leading to graft loss. Primary nonfunction occurred in one case (4%). By splitting 24 of 87 transplantable livers (4 of which were in partner units), a total of 111 transplantations were performed, increasing graft availability by 28%.

CONCLUSIONS

Split-liver transplantation is achieving graft and patient survival rates similar to that of whole liver transplantation despite a higher incidence of complications, which could become less frequent as experience is gained with this procedure. A wider acceptance of split-liver transplantation could markedly increase the supply of liver grafts.

Monosegmental liver transplantation from an adult to an infant

A shortage of small pediatric organ donors has led to the development of reduced size liver transplantation in children. However, the discrepancy between donor and recipient weight can limit the use of this procedure despite transplantation of the left lobe only. Monosegmental liver transplantation using segment III only was recently described. We report here the case of an 11 month old, 6.9 kg boy who received another monosegmental graft (segment II) from a 78 kg donor on an urgent basis. Because of the lack of parenchymal landmarks between segments II and III, sterile methylene blue solution was injected into the portal vein of segment III: parenchyma of this segment colored immediately and was resected accordingly. Three and a half years later, the growth, development, and nutrition of this child were normal. This procedure seems to be helpful when the left lobe of the graft is obviously too large.

Liver transplantation in children with chronic end stage liver disease: factors influencing survival after transplantation

To identify pretransplant factors that are influencing survival after orthotopic liver transplantation a Cox proportional hazards regression model was applied to 118 children with chronic terminal liver failure transplanted at Medical School Hannover during the period of 1978 to 1994. The response variable was survival, as covariates a total of 19 pretransplant variables were entered--i.e. age, diagnosis (biliary cirrhosis, metabolic cirrhosis, postnecrotic cirrhosis, cryptogenetic cirrhosis) sex, laparotomy prior to OLT, height, weight, standard deviation scores for height and weight, date of first OLT, serum alanine aminotransferase, asparagine aminotransferase, albumin, total bilirubin, cholinesterase activity, glomerular filtration rate, and prothrombin time. Significant independent predictors of survival after OLT were bilirubin (P=0.0024), SDS for weight (P=0.034), and albumin (P=0.039). In a subsequent discriminant analysis cut off points for these variables could be identified--i.e., bilirubin >340 micromol/L, SDS for weight <-2.2 and albumin < 33 g/L. Patients with one or more of these risk factors were grouped as urgent indication group (n=76) and those with no risk factor as elective indication group (n=42). Comparing the posttransplantation survival in these groups there is a statistically significant difference at 1 year (57% vs. 90.5%) and 4 years (49% vs. 90.5%) after OLT (P=0.0001, log rank test). It is concluded that the risk of OLT is much higher if liver function is very poor. Optimal nutritional support prior to transplantation is mandatory to optimise the clinical status of the children and to improve the results of OLT.

In situ splitting of cadaveric livers. The ultimate expansion of a limited donor pool

OBJECTIVE

The authors evaluate the safety, applicability, and effectiveness of a new technique for split-liver transplantation.

SUMMARY BACKGROUND DATA

Split-liver transplantation offers an attractive way to increase the donor pool for cadaveric liver transplantation. The application of this concept has been hampered by inferior patient and graft survivals and higher complication rates. Without supportive data, the concern about increasing biliary leakage and poor initial graft function persisted. The authors focused on the causes of these complications by presenting a new technique to eliminate these problems.

METHODS

Liver splitting was performed in the heart-beating cadaveric organ donor, using the technique described for procurement of the left lateral lobe of a live donor. A detailed description of the technique is presented. A retrospective review of the first 14 transplantations resulting from 7 in situ splitting procedures was collected. The results were compared with 19 conventional split-liver transplants performed during the same period.

RESULTS

Six-month patient and graft survivals after in situ split-liver transplantation were 92.8% and 85.7%, respectively. Biliary complications were absent. Postoperative courses were mostly uneventful and characterized by lower peak transaminase levels compared with standard techniques. Early graft function of extrahepatic organs procured simultaneously was excellent.

CONCLUSIONS

In situ split-liver transplantation provides superior results, related mainly to reduction of cold ischemic damage of the grafts and avoidance of biliary complications. In situ split-liver transplantation renders graft reduction alone obsolete and opens a donor pool for adults to receive right lobes safely. It allows for long-distance sharing between pediatric and adult liver transplant units because the procedure abolishes ex situ benching and prolonged ischemia time and provides two anatomically perfect grafts with hemostasis accomplished.

Paediatric liver transplantation: a 10 year experience in Taiwan

Between March 1984 and August 1994, 13 orthotopic liver transplantations were performed in 13 patients < or = 25 years of age. The indications included Wilson's disease (n = 7), biliary atresia (n = 4), choledochal cyst (n = 1) and hepatitis C cirrhosis (n = 1). Technical variants included full-size (n = 11), reduced-size (n = 1) and living-related (n = 1) liver transplantation. These recent technical innovations have offered an expanded donor pool for earlier transplantation, shorter waiting times and excellent quality grafts. Surgical complications occurred in six patients; all required additional surgery. Biliary complications were encountered more commonly in our earlier patients. Our actuarial patient and graft survival rate is 92% at 2 years. The long-term follow-up of our liver-transplanted Wilson's disease patients provides confirmatory evidence that orthotopic liver transplantation cures the underlying metabolic defect with complete normalization of biochemical abnormalities of copper metabolism, reversal of neurological impairments and the disappearance of Kayser-Fleischer corneal rings. The high rate of patient survival and excellent rehabilitation indicate that with prudent clinical judgement, liver transplantation can be achieved with an acceptable rate of morbidity, mortality and cost in a setting where manpower and donor organs are very limited.

One year of experience with extended application and modified techniques of split liver transplantation

As organ donation rates decreased in Europe, the authors started a systematic approach of liver splitting in their center in 1994. During this 1-year experience, 73 cadaveric liver transplantations were performed in 66 patients. Sixteen of these transplantations were the result of split-liver transplantation (21.9% of grafts, 24.2% of patients). Patient and graft survival rates at 3 months were 81.2% and 75%, compared with 89.1% and 76.9 % for whole organs. Two modified techniques were developed, based on the technique of living related liver procurement, and applied in 10 cases. With these new techniques, patient and graft survival rates were 90% and 90%. This systematic approach allowed the total number of transplantations in our program to be maintained, despite the decrease in organ availability.

Calculation of child and adult standard liver volume for liver transplantation

Despite refinements in surgical techniques for liver transplantation, liver size disparity remains one of the most common problems in pediatric patients. Optimal liver graft size remains unknown and the volume of diseased liver in the recipient is not indicative of the volume (standard liver volume [LV]) optimal for the recipient's metabolic demands. To establish a formula for calculating the standard LV in the pediatric and adult populations for liver transplantation, whole LVs were measured using computed tomography (CT) in 96 patients (65 pediatric and 31 adolescent or adult subjects) with normal liver whose disease conditions did not seem to affect body weight (BW) or LV. In the 96 subjects, the ratio of estimated LV to BW decreased gradually as age increased until approximately 16 years, when it started to level off. On the other hand, there seemed to be a directly proportional relationship between the estimated LV in vivo and body surface area (BSA) (r = .981; r2 = .962; P < .0001) in the subjects as a whole, and the formula, LV (mL) = 706.2 x BSA (m2) + 2.4, was established from the measured data by simple regression analysis. Another predicting equation, LV (mL) = 2.223 x BW (kg)0.426 x body height (BH) (cm)0.682, was produced by multiple regression analysis (r2 = .969; P < .0001). Considering its simplicity of use, we adopted the first formula for predicting standard LV in an individual patient.

Reduced-size hepatic allografts

Reduced-size hepatic transplantation (RSHT) was developed to alleviate the mortality resulting from the scarcity of suitable cadaveric grafts. RSHT consists of various techniques that reduce a full liver to a smaller size. These techniques include reduced-size cadaveric liver transplantation (RLT), split liver transplantation (SLT), and living-related liver transplantation (LRLT). RLT utilizes part of a liver, while the rest is discarded; in SLT, the whole liver is used for two recipients after bipartition; and in LRLT, a portion of the liver retrieved from a living donor is transplanted. Whereas RLT only redistributes the pool of organs to the advantage of pediatric recipients, both SLT and LRLT increase the availability of grafts for transplantation. RSHT yields results comparable to full-liver allografting and drastically reduces the mortality of patients waiting for transplantation. The procedures involved are technically demanding and should be restricted to experienced liver centers.

New techniques for liver transplantation: reduced-size, split-liver, living-related and auxiliary liver transplantation

Mortality among patients on a waiting list for orthotopic liver transplantation continues to be 10-15%; this is of particular concern in the pediatric population and may become more problematic in adult patients as longer waiting lists for cadaveric transplantation accrue. The longer cold ischemia times afforded by use of University of Wisconsin (UW) solution and improved hepatic surgery techniques have allowed the development of reduced-size liver transplantation (RSLT), split-liver transplantation (SLT), and living-related liver transplantation (LRLT). These new surgical techniques have been predominantly employed in children, up to 40% of whom may be candidates for one of these modified procedures. With the exception of SLT, these approaches have been associated with comparable rates of biliary tract and vascular complications, rejection episodes and graft and patient survival when compared to whole organ transplantation. Right hepatic lobe graft recipients have approximately 15% decreased graft survival rates, limiting the acceptance of SLT as a standard approach to decrease waiting list times. Application of LRLT to the adult population, where 5-10% of recipients are potential candidates, is expected to increase. Over 100 LRLTs have been performed worldwide and while recipient survival with LRLT is excellent, concerns about donor morbidity and mortality, psychosocial factors and reimbursement issues remain obstacles. Living-unrelated liver transplantation and auxiliary orthotopic partial liver transplantation are developing approaches to be considered only in highly selected cases.

Reduced size liver transplantation, split liver transplantation, and living related liver transplantation in relation to the donor organ shortage

Because of the shortage of cadaveric donors, three techniques of partial liver grafting have been developed. These techniques are placed in perspective in relation to the organ shortage. Reduced size liver transplantation (RSLTx) is widely used and has results comparable to those from whole liver grafting. However, this technique, while benefitting pediatric patients, reduces the adult donor liver pool. It also makes inefficient use of an available adult donor liver. In split liver transplantation (SPLTx), the whole liver is used after bipartition for two recipients. The results are comparable to those of RSLTx. The problem with SPLTx is that it is a very demanding technique applied only in centers with extensive experience with liver resection and reduction. Living related liver transplantation (LRLTx) yields excellent results; however, it places an otherwise healthy person at risk. It is argued that instead of performing risky operations on healthy persons, the health authorities should take specific measures to alleviate the organ shortage. In the meantime, SPLTx should be developed further because of its optimal use of donor tissue. As for LRLTx, its excellent results and the present shortage of size-matched pediatric liver donors justify its use, at least for now.

Liver transplantation: newer surgical approaches

The standard procedure for orthotopic liver transplantation remains transplantation of the whole organ together with resection of the vena cava and the use of venovenous bypass. In cases of severe mismatch of the donor and recipient vena cava, the piggyback technique, if necessary with vena cava plasty, is preferable. Furthermore, in all cases where venovenous bypass cannot be performed, the piggyback or other technique preserving the vena cava should be performed. In paediatric patients, reduced/size liver transplantation may be indicated because of the shortage of small livers. In the hands of experienced surgeons, the results of reduced-size liver transplantation in paediatric patients are similar to those of whole organ transplantation. Further innovative procedures to overcome the problem of organ shortage include split-liver and living related transplantation in children. Distinct advantages of living related transplantation can be seen in a well-functioning graft, lack of preservation injury, elective operation and optimal graft-size matching. The immunological advantage that has been claimed could not be demonstrated so far, and will need to be examined in the long-term follow-up. However, there remains a distinct disadvantage for living related transplantation with regard to the surgical technique. Preoperative portal venous thrombosis should be carefully assessed, but is not a contraindication to liver transplantation if the confluence of the superior mesenteric vein and splenic vein is patent. Arterial reconstruction at the confluence of two arteries (hepatic and gastroduodenal or splenic artery) seems to be preferable to an end-to-end anastomosis because of improved inflow into the graft and a reduced risk of arterial stenosis and thrombosis. Where the common hepatic arteries are small, with reduced or reversed flow, and in patients with coeliac trunk stenosis, we recommend a direct approach to the suprarenal or infrarenal aorta. Bile duct anastomosis may preferably be performed with a side-to-side technique, to reduce early and late biliary complications.

Sequential treatment of biliary atresia with Kasai portoenterostomy and liver transplantation: a review

Biliary atresia is the most frequent cause of chronic cholestasis in infants. When left untreated, this condition leads to death from liver insufficiency within the first 2 yr of life. The modern therapeutic approach consists of a sequential strategy with Kasai portoenterostomy as a first step and, in case of failure, liver transplantation. After portoenterostomy, no more than 20% to 30% of patients will live jaundice-free into adulthood. Illness in another third will be palliated, and these patients have extended survival, delaying liver transplantation to later childhood (2 to 15 yr). The remaining 30% to 40% will not benefit from the Kasai operation and will die of liver failure in infancy. The annual need of liver transplantation for biliary atresia is one case per million people. This indication represents 35% to 67% of the reported series of pediatric liver transplantation and between 5% and 10% of the indications for liver transplantation, all ages included. Approximately four of five children transplanted for biliary atresia will become long-term survivors with good physical and mental development; recurrence of the disease after transplantation has not been observed. Because most candidates are young children (< 3 yr) of small size (< 10 kg), there is a shortage of size-matched donors (which has been alleviated by the use of innovative techniques such as reduced and split livers). The resulting redistribution of the adult donor liver pool is ethically justified by the equal quality of the results after transplantation of a full-size or partial graft.

Living donor for liver transplantation

Since living related liver transplantation was first performed in 1989, more than 150 cases have been performed worldwide, mostly in the United States and Japan. This paper reports the first series of living related liver transplantation in Europe. Twenty living related liver transplantation surgeries were performed over a 13-mo period, with an overall patient survival of 85%. For patients who underwent elective transplantation (n = 13), the survival rate was 100%. Technical complications included one arterial thrombosis necessitating retransplantation and five bile leaks requiring surgical revision. The technical improvements that permit avoidance of these complications are discussed. A detailed description of the living related liver procurement is given. All procurements yielded grafts of excellent quality. No intraoperative complications occurred, and no reoperations were necessary. No heterologous blood transfusion was needed. In two patients, incisional hernias developed after wound infection. Living related liver transplantation does not absolve the transplant community of efforts to promote cadaveric organ procurement. Nevertheless, living related liver transplantation does have the advantage of a readily available graft of excellent quality, permitting transplantation with optimal timing under elective conditions. Several centers are now preparing living related segmental liver transplants, following the model of our protocol, for three reasons: (a) to obtain superior results compared with cadaveric liver transplantation; (b) to overcome cadaveric organ shortage and further reduce pretransplantation mortality and (c) to provide viable organs in countries where cadaveric organ procurement is not established. When performed by a team experienced in pediatric liver transplantation and in adult liver resection, living related liver transplantation is an excellent modality for the treatment of end-stage liver disease in children.

Indications for liver transplantation in hepatobiliary malignancy

Our personal experience with 172 patients, the results from the European Liver Transplant Registry and a review of the recent literature are summarized and discussed to define present indications for liver transplantation in hepatobiliary malignancy. The following conditions should be considered contraindications: advanced primary liver tumors with any extrahepatic spread, cholangiocellular carcinoma, hemangiosarcoma and liver metastases from nonendocrine primary tumor. Currently, "favorable" indications include uncommon tumors such as fibrolamellar carcinoma, epithelioid hemangioendothelioma, hepatoblastoma and metastases from endocrine tumors. Further indications may be nonresectable hepatocellular and proximal bile duct carcinoma in tumor stage II. Borderline indications are hepatocellular and proximal bile duct carcinoma in tumor stage III. In advanced tumors confined to the liver, transplantation should be restricted to multimodality treatment protocols. Although there are strong arguments for transplantation in early resectable hepatocellular carcinoma with underlying cirrhosis, it remains an open issue requiring further investigation in a controlled study using the same tumor classification. With regard to limited resources of donor organs, split-liver transplantation permits transplantation in tumor patients without neglecting those with benign diseases.

Preoperative measurement of segmental liver volume of donors for living related liver transplantation

Segmental liver volume determination by computed tomographic scan was carried out preoperatively in nine donors for living related liver transplantation. The calculated volume was compared with the graft size actually obtained by three types of donor hepatectomy. The volume of the left lateral segment (175 to 241 ml) and the left lobe (310 to 490 ml) varied markedly among the donors. The ratio of the left lobar to total liver volume also showed a wide range of values (23.2% to 35.9%). The value of the left lobar volume did not correlate positively with the donor's body weight, suggesting that graft size cannot be predicted only on the basis of the donor's body size. Segmental graft liver volume was estimated by use of computed tomographic scan, with acceptable accuracy on comparison with the graft volume actually obtained. In living related liver transplantation, the type of donor hepatectomy should be selected on the basis of the segmental liver volume of the donor in addition to the recipient's body size so that liver failure can be prevented in recipients and the donor's safety can be assured as far as possible.

A new animal model for split liver transplantation using an infrahepatic IVC graft

An animal model of split liver transplantation using pigs is described herein. The donor liver was divided into two grafts, the right graft consisting of the right medial and lateral segments with the caudate lobe, and the left graft consisting of the left lateral and medial segments. To make implantation easier, a distal part of the donor's inferior vena cava (IVC) was isolated and attached to the left graft with an anastomosis between the orifice of the renal vein and the graft's hepatic vein. The left graft thereby contained a newly constructed retrohepatic IVC for anastomosis to the recipient. During the anhepatic phase, no conventional bypass procedure was used, but an abdominal aortic clamp in combination with general hypothermia was employed. Ten pigs were used as donors and a total 20 liver transplantations performed. No immunosuppressive drugs were given in this series. Ten of the 20 recipients survived for more than 2 days, the mean survival time being 4.7 days, with a range of 2-14 days. The mean survival time of the left grafts was much longer than that of the right grafts, although no technical problems such as kinking of the graft or occlusion of the hepatic vein were encountered in either. This model is the first report of split liver transplantation in animals. The advantages of using the infrahepatic IVC graft include stability of the graft and safe hepatectomy. This model will therefore be useful for the experimental study of split liver transplantation and may also be employed for clinical use in the future.

Controlled liver splitting for transplantation in two recipients: technique, results and perspectives

A technique of controlled liver splitting for transplantation in two recipients is proposed, based on a full anatomical assessment of the graft including arteriography and cholangiography on the back-table. Using eight livers, 16 patients received a graft: right liver (eight patients), left lobe (four) or left liver (four). Twelve patients required urgent or very urgent transplantation. Anatomical assessment of the graft demonstrated a portal bifurcation in all cases, a common trunk of the left and middle hepatic veins in five, a right biliary duplication in three and duplication of the left branch of the middle hepatic artery in one. After revascularization of the graft, bleeding was greater in patients with a right graft, particularly if the middle hepatic vein had been ligated. The main postoperative complications were hepatic artery thrombosis (four cases), biliary complications (four), portal vein thrombosis (two), haematoma (two) and abscess (two). No primary non-function of the graft was observed. The postoperative survival rate was 75 per cent. The four patients in whom transplantation was not considered urgent are still alive. The immediate survival rate of the grafts was 69 per cent. These results compare favourably with those in the literature. In spite of the technical, logistical and ethical problems raised by this technique, the results suggest that controlled liver splitting for transplantation in two recipients may in the future significantly improve the feasibility of liver transplantation.

One liver for two: partition of the portal elements

A cadaver liver is divisible into two transplants by section between right and left lobes, or section between left medial segment and left lateral segment medial to the umbilical cleft. To establish the ideal basis of partition of the portal elements, an anatomic study of 33 livers was performed. It is preferable to section the left portal vein, longer and more constant than the right, the right branch of the hepatic artery, larger and more constant than the left, and the left hepatic duct because of the vascularization of the common hepatic duct. To use the length of the left portal vein, it is necessary to section all its branches to segment I and then to resect this segment. After a section between the left medial segment and the left lateral segment medial to the umbilical cleft, the left medial segment always loses its total portal venous vascularization and should be resected. Before a split-liver, cholangiography and arteriography should be performed to detect anatomical variations without performing an extensive dissection which may endanger the vascularity of the bile ducts.

Emergency liver transplantation for fulminant liver failure in infants and children

We report our results with orthotopic liver transplantation in children with fulminant liver failure. Thirty-five children with fulminant liver failure were evaluated for liver transplantation. The main causes of liver failure were viral hepatitis (54.2%), drug-induced liver injury (14.2%) and Wilson's disease (11.4%). Children were considered as candidates for liver transplantation only if hepatic encephalopathy was associated with a decrease in the level of factor V to below 25%. Seven children (20%) did not meet this criterion and recovered spontaneously. Six children (17.1%) had contraindications for liver transplantation and died. In three of these six children, contraindications included irreversible brain damage at the time of admission. Twenty-two children (62.8%) met the criteria for liver transplantation and were placed on the emergency transplant list. Three of them died awaiting grafts. Nineteen children underwent liver transplantation; 13 of them (68.4%) are alive without sequelae, after 6 mo to 4 yr of follow-up, at this writing. Four of the children who died after surgery had severe encephalopathy on admission that did not improve after liver transplantation. In conclusion, emergency liver transplantation appears to be an effective treatment for children with fulminant liver failure. Nevertheless, irreversible brain damage developed in 10 patients, and they died before or after surgery. We postulate that many of these deaths could have been avoided if children had been transferred to a liver transplantation facility and had undergone transplantation earlier. We emphasize that children with acute liver failure should be transferred to a center that performs liver transplantation before the development of hepatic encephalopathy.

Hepatic transplantation in children using reduced size allografts

The shortage of paediatric liver donors has led to the use of reduced size hepatic allografts. Between July 1987 and July 1990, 30 reduced size orthotopic liver transplantations were performed in 24 children aged between 3 months and 7 years. All patients were in advanced chronic or acute liver failure and were considered unlikely to survive for long enough for a size-matched donor to become available. The most common indication was biliary atresia. The median intraoperative blood loss was 75 (range 13-1015) ml kg-1. Nine patients have died and seven have undergone retransplantation, four successfully. Seven patients had portal vein hypoplasia with a high graft failure rate due to ischaemic infarction. There was significant morbidity from biliary tract complications, leading to further operations in four cases. The 1-year actuarial survival rate was 62 per cent.

Liver transplantation for hepatocellular carcinoma: clinical results and future aspects

The treatment of unresectable hepatocellular carcinoma (HCC) by liver transplantation remains controversial. In our series, the 5-year survival value for 87 patients who underwent transplantations between 1972 and 1990 was 19.6%. There was no difference in the long-term survival of patients who had underlying cirrhosis and those who did not. In patients with early-stage tumors the long-term prognosis was improved, the 5-year survival in stage II disease being 55.6% according to UICC criteria. Even in some cases of more advanced tumour stage, good long-term results were obtained. In a review of the recent literature, we evaluated prognostic factors to work out criteria for a more differentiated indication for liver transplantation. Resection of increased radicality--which will keep its place as the therapy of choice--and transplantation should be performed complementarily. Further developments will reveal the value of multimodal therapeutic strategies, including chemo-embolisation, chemotherapy and immunotherapy.

Can liver transplantation be applied for the treatment of liver cancer?

Unfavourable results and shortage of donor organs have led to restricted indication of liver transplantation for irresectable hepatocellular carcinoma. This review analyses the current state of experience in order to work out criteria for a more differentiated multimodal treatment including liver transplantation. New techniques of extended liver resection under hypothermic perfusion have to be considered in some conventionally irresectable tumors. Split-liver transplantation is a donor organ saving option which preserves the chance of transplantation in individual tumor patients without disadvantage for patients with benign diseases.

Living related liver transplantation

Liver transplantation from a brain death donor has not yet been accepted in Japan. The only alternative method at present is transplantation from a living donor. After the first successful living related liver transplantation was performed by Strong in Brisbane, Australia, Japanese hepatic and transplant surgeons also began to perform such operations. As of February 1991, 16 living related liver transplantations had already been performed in Japan, mainly for children with biliary atresia. Five of these patients subsequently died, however, our patient has survived more than 1 year, and she is presently leading a normal school life. The most important issue regarding living related liver transplantation is to ensure the donor's safety. For this purpose, we conducted a preoperative banking of the donor's own blood and plasma. In addition, a selective vascular occlusion was carried out to reduce blood loss during the resection of the liver. Intraoperative color Doppler ultrasonography was introduced for evaluating the circulation of the graft. By using this modality, the following three points were able to be accurately estimated in order to obtain optimal graft perfusion: 1) The most suitable position for the graft to be fixed to the abdominal wall, 2) whether or not the abdominal wall could be closed and 3) the indication for a ligation of the collateral veins to form a porto-systemic shunt. Thanks to these procedures, living related liver transplantations have now become an acceptable transplant method, however, a transplantation from a cadaver that is brain dead but still has a beating heart is still absolutely necessary for adult recipients. Therefore, in the future, both methods should be performed.

Technique and preliminary results of extracorporeal liver surgery (bench procedure) and of surgery on the in situ perfused liver

The clinical experience with 11 patients undergoing ex situ operation of the liver (nine operations) or surgery on an in situ hypothermic perfused liver after vascular isolation (three operations) is described. These methods have been confined to situations and tumour stages otherwise deemed untreatable, or to situations where resection would not have been sufficiently radical. In one patient the ex situ approach avoided the need to undertake liver grafting for a benign tumour. To date, hepatocellular tumours and metastases not compromising global hepatic function or causing cholestasis are considered to be suitable conditions; cholestasis appears to be highly detrimental for the postoperative course after an ex situ procedure. Elaboration of methods for better grading of pre-existing liver damage and of its prognostic significance is essential. The assessment of the final therapeutic value of the described procedure requires further experience.

[Liver transplantation in low portal vein flow: separation of portal vein areas with divided portal-venous and arterialized caval-venous liver perfusion. 1. Clinical case report]

A new method for the performance of a hepatic transplantation in spite of a low portal blood flow situation is described casuistically. In a 36-year-old-patient suffering from liver cirrhosis due to hepatitis B, the portal blood system of the right and left liver parts were divided, the left part was perfused with a low flow of portal blood, the right one with arterialized caval blood. The function of the transplanted liver and the early postoperative course were excellent. During the further postoperative course portal perfusion presumably diminished or stopped on the left side from three weeks and on the right side from two months postoperatively. Nevertheless the general condition of the patient improved continuously; transient elevations of transaminases may reflect the disturbance of portal perfusion. The technique of this arterialized caval blood perfusion of the portal system is presumably applicable also for situations, in which there is no portal blood flow available for perfusion of a liver graft. Thus, the absence of possibility for reconstruction of portal blood inflow or a situation with a hypoplastic portal vein may no longer be considered as a technical contraindication for liver grafting.

Emergency orthotopic liver transplantation in two patients using one donor liver

Because of its anatomy, the liver can be divided into two hemilivers suitable for use as two grafts for liver transplantation. The line of division is the main scissure, giving the right hemiliver (segments 5-8) and the left hemiliver (segments 2-4). Segment 1 (caudate lobe) has to be resected. The vessels are divided between the two grafts: the vena cava remains on the right; on the left, the left hepatic vein is sutured into the vena cava of the recipient, which is retained intact. The left graft retains only the left branch of the portal vein, the bile duct and the hepatic artery. The right graft retains the portal trunk, the common bile duct and the right branch of the hepatic artery. This procedure was used for emergency grafting of two patients with fulminant hepatitis when only one donor was available. Both recipients recovered from coma and regained normal liver function. However, both died from causes not specifically related to the operative technique, one from multiple organ failure on the 20th day and the other from diffuse cytomegalovirus infection on the 45th day.