Living donor liver transplantation

Abstract

In the 1960s and the 1970s, liver transplantation was slowly developed to become a feasible option in the treatment of end-stage liver disease. By 1984, the results of the first series performed throughout the world were deemed good enough to consider liver transplantation as an accepted treatment for these patients [[1]Starzl T.E. NIH Consensus Development Conference Statement: Liver Transplantation.Hepatology. 1984; 4: 1075Crossref Google Scholar]. If until then, liver donor shortage was not a major problem, this was going to change radically in the following decade. The number of liver transplantations performed per year rose at an exponential pace both in Europe and in the American continent. Finally, this growth was limited by an increasing shortage of donors, leading to prolonged waiting times and high mortality on the waiting list. At the same time, the development of the knowledge of segmental anatomy of the liver and in particular the systematic description by Couinaud contributed very much to liver surgery [[2]Couinaud C. Le Foie- Etudes anatomiques et chirurgicales. Masson and Cie, Paris1957Google Scholar]. Based on this knowledge, anatomical liver resections, respecting the vascular perfusion of the remaining segments, could be performed. Very early it was realised that this would open the road for reduced graft liver transplantation, split-liver transplantation and even living donation [3Smith B. Segmental liver transplantation from a living donor.J Pediatr Surg. 1969; 4: 126-132Abstract Full Text PDF PubMed Google Scholar, 4Dagradi A. Marzoli G.P. Radin S. Sussi P.L. Dagradi V. Zannini M. et al.Possibilities of sectional liver transplantation in man.Langenbecks Arch Chir. 1968; 322: 533-537Crossref PubMed Scopus (4) Google Scholar]. In 1984, the first successful transplantation of a partial liver allowing the transplantation of a child with part of the liver of a larger donor, was reported by Bismuth [[5]Bismuth H.H.D. Reduced-size orthotopic graft in hepatic transplantation in children.Surgery. 1984; 95: 367-370PubMed Google Scholar]. In 1988, both the teams of Hanover and of Paris [6Pichlmayr R. Ringe B. Gubernatis G. et al.Transplantation einer Spenderleber auf zwei Empfänger: (Spli liver transplantation) Eine neue Methode in der Weiterentwicklung der Lebersegmenttransplantation.Langenbecks Arch Chir. 1989; 373: 127-130Crossref Scopus (0) Google Scholar, 7Bismuth H. Morino M. Castaing D. Gillon M.C. Descorps Declere A. Saliba F. et al.Emergency orthotopic liver transplantation in two patients using one donor liver.Br J Surg. 1989; 76: 722-724Crossref PubMed Google Scholar] managed to divide a liver into two grafts, allowing successful transplantation in two recipients. The practical feasibility of split-liver transplantation as well as the increased safety of conventional liver surgery suddenly opened up the idea of removing part of the liver from a living donor to transplant it in a smaller recipient. Intensive ethical consultations took place at the University of Chicago to determine how uncoerced consent could be obtained and under which conditions a trial with such a surgical procedure could be started [8Singer P.A. Siegler M. Whitington P.F. Lantos J.D. Emond J.C. Thistlethwaite J.R. et al.Ethics of liver transplantation with living donors.N Engl J Med. 1989; 321: 620-622Crossref PubMed Google Scholar, 9Singer P.A. Siegler M. Lantos J.D. Emond J.C. Whitington P.F. Thistlethwaite J.R. et al.The ethical assessment of innovative therapies: liver transplantation using living donors.Theor Med. 1990; 11: 87-94Crossref PubMed Google Scholar, 10Singer P.A. Lantos J.D. Whitington P.F. Broelsch C.E. Siegler M. Equipoise and the ethics of segmental liver transplantation.Clin Res. 1988; 36: 539-545PubMed Google Scholar]. First cases were performed in 1989 in Australia and in South America [11Strong R.W. Lynch S.V. Ong T.H. Matsunami H. Koido Y. Balderson G.A. Successful liver transplantation from a living donor to her son.N Engl J Med. 1990; 322: 1505-1507Crossref PubMed Google Scholar, 12Raia S. Nery J.R. Mies S. Liver transplantation from live donors.Lancet. 1989; 2: 497Abstract PubMed Google Scholar] and finally a first series was produced under close institutional control by Broelsch et al. in Chicago [13Brolsch C.E. Stevens L.H. Whitington P.F. The use of reduced-size liver transplants in children, including split livers and living related liver transplants.Eur J Pediatr Surg. 1991; 1: 166-171Crossref PubMed Google Scholar, 14Broelsch C.E. Emond J.C. Whitington P.F. Thistlethwaite J.R. Baker A.L. Lichtor J.L. Application of reduced-size liver transplants as split grafts, auxiliary orthotopic grafts, living related segmental transplants.Ann Surg. 1990; 212 (discussion p. 375–376): 368-375Crossref PubMed Google Scholar]. The procedure was taken over in Europe (Fig. 1) and further developed in Japan, where, because of the unavailability of cadaveric donation, it encountered a huge success [[15]Ozawa K. Uemoto S. Tanaka K. Kumada K. Yamaoka Y. Kobayashi N. et al.An appraisal of pediatric liver transplantation from living relatives. Initial clinical experiences in 20 pediatric liver transplantations from living relatives as donors.Ann Surg. 1992; 216: 547-553Crossref PubMed Google Scholar]. Despite initial heavy criticism in the Western world, living donation soon proved to be an inevitable development if one was to run a successful paediatric transplant program. Indeed, in centres performing both split-liver transplantation and living donor liver transplantation (LDLT), mortality of children on the waiting list fell to almost zero [16de Ville de Goyet J. Reding R. Sokal E. Otte J.B. Related living donor for liver transplantation in children: results and impact.Chirurgie. 1997; 122: 83-87PubMed Google Scholar, 17Rogiers X. Malago M. Gawad K. Jauch K.W. Olausson M. Knoefel W.T. et al.In situ splitting of cadaveric livers. The ultimate expansion of a limited donor pool.Ann Surg. 1996; 224 (discussion p. 339–41): 331-339Crossref PubMed Scopus (226) Google Scholar]. The success in paediatric liver transplantation and the shortage of organs provided the necessary incentive to attempt living donation for adults. The emerging awareness of the importance of graft volume and the suboptimal results with smaller grafts, even when transplanted as auxiliary grafts [18Kiuchi T. Kasahara M. Uryuhara K. Inomata Y. Uemoto S. Asonuma K. et al.Impact of graft size mismatching on graft prognosis in liver transplantation from living donors.Transplantation. 1999; 67: 321-327Crossref PubMed Scopus (507) Google Scholar, 19Broering D. Orth S. Kim J. Hillert C. Broelsch C. Helmke K. et al.Results after pediatric liver transplantation depend on the transplanted liver volume.Langenbeck Arch Chir. 2000; 352 (Kongreßband, 2000): 543Google Scholar], made surgeons move to developing right lobe liver donation for transplanting larger children or adults [20Yamaoka Y. Washida M. Honda K. Tanaka K. Mori K. Shimahara Y. et al.Liver transplantation using a right lobe graft from a living related donor.Transplantation. 1994; 57: 1127-1130PubMed Google Scholar, 21Lo C.M. Fan S.T. Liu C.L. Wei W.I. Lo R.J. Lai C.L. et al.Adult-to-adult living donor liver transplantation using extended right lobe grafts.Ann Surg. 1997; 226 (discussion p. 269–70): 261-269Crossref PubMed Scopus (402) Google Scholar]. Despite concerns of donor morbidity and mortality, this procedure has opened up the possibility of living donation to the adult patients with end-stage liver disease and has been on a rapid rise in the last few years. Living liver donation certainly counts amongst the great surgical achievements of the 20th century and has saved the lives of many patients. Living donor transplantation has been accompanied by an ethical debate from its earliest days on, even before it started the first series. The Chicago program set an example for the handling of innovative procedures by publishing the ethical discussion and demanding criticism from the medical community [[8]Singer P.A. Siegler M. Whitington P.F. Lantos J.D. Emond J.C. Thistlethwaite J.R. et al.Ethics of liver transplantation with living donors.N Engl J Med. 1989; 321: 620-622Crossref PubMed Google Scholar] prior to actually performing the procedure. During this time, the emphasis of the ethical discussion was on two major issues: how can such an innovative procedure be introduced into a first study and how should informed consent be obtained. Almost 10 years later, living donation for adult recipients was started with much less ethical discussion. Ethical considerations were first published [[22]Malago M. Testa G. Marcos A. Fung J.J. Siegler M. Cronin D.C. et al.Ethical considerations and rationale of adult-to-adult living donor liver transplantation.Liver Transpl. 2001; 7: 921-927Crossref PubMed Scopus (74) Google Scholar] after many cases had been performed. The emphasis here was more on the field strength needed before one can embark on this procedure and on the issue whether LDLT can be justified for indications, presently considered as contraindications for cadaveric liver transplantation. It is important to be aware that living donation for adults takes place in a different dimension from that for children. The donor operation carries a higher risk, whereas the recipient, especially with advanced stage of disease, may have an inferior prognosis. The donor–recipient relationship is usually not that of parent to child. The adult recipient can pressurise his donor more easily. This is not only because he can speak and act independently, but also, facing the risk of death (this is also a major difference to the situation of living kidney donation), he may himself search for a suitable willing donor (whereas the donation from parent to a small child is a spontaneous gift). This anxiety may increase as the recipient's condition deteriorates. Even the possibility that the donor may become aware of his or her refusal of donation adds a substantial amount of coercion. Finally, in contrast to the parent–child situation, the donor may expect excessive gratitude from his adult recipient. For this reason, non-coerced consent is more difficult to obtain. At the same time, the donor is facing a larger donor operation with more risks of short- or long-term complications. It is the view of the authors that these circumstances demand exceptional carefulness of the physicians involved in informing and evaluating the living donor (Table 1).Table 1Main differences between living donation for a paediatric and adult recipientPaediatricAdultDonor–recipient relationshipUsually genetically relatedGenetically or emotionally relatedRecipientNo decision capabilityDecision capabilityCannot request donationCan request donationCannot refuse donationCan refuse donationDonor risk+++Graft/recipient liver volumeVariableSmall-for-sizeRecipient risk−Graft sizeRecipient conditionBiliary complicationsEarly Hepatitis C recurrenceSurgical skill requirements+++++ Open table in a new tab Donors of recipients suffering from emergency fulminant hepatitis should undergo extensive counselling and psychosocial evaluation because the urgency of the situation may not allow sufficient time to fully comprehend and give a truly informed consent [[23]Schiano T.D. Kim-Schluger L. Gondolesi G. Miller C.M. Adult living donor liver transplantation: the hepatologist's perspective.Hepatology. 2001; 33: 3-9Crossref PubMed Scopus (76) Google Scholar]. LDLT in this setting needs daily careful balancing of the donor's risk and the likelihood of acquiring an ABO-compatible cadveric graft. The medical and anatomical evaluation of the donor should not be different from that prior to donation for an elective recipient despite pressure of time and should be started preferable even before listing the patient for high urgency transplantation. Information about the possibility of living donation is an integral and obligatory part of the general information that should be given to liver transplant candidates. The possibility should not be pushed actively, however [23Schiano T.D. Kim-Schluger L. Gondolesi G. Miller C.M. Adult living donor liver transplantation: the hepatologist's perspective.Hepatology. 2001; 33: 3-9Crossref PubMed Scopus (76) Google Scholar, 24Pszenny C. Krawczyk M. Paluszkiewicz R. Hevelke P. Zieniewicz K. Grzelak I. et al.Biochemical function of the donor liver in living related liver transplantation.Transplant Proc. 2002; 34: 621-622Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar], since it is important that patients and their families feel no pressure in seeking an appropriate person for donation. The ideal situation is one in which the potential donor spontaneously presents himself for evaluation. Fortunately, this situation is becoming increasingly welcome because transplant recipients and their families are better informed about the option of living donation by their local doctor, patient organisations, the internet or public media. In Germany, LDLT is not limited to blood-born relatives, but all persons who have a close, long-term emotional relationship with the recipient are accepted. In contrast, in France the procedure is limited to first-degree relatives. In some countries (USA), living donation between non-relatives is also allowed. Potential donors should have a blood group compatible with that of the recipient (with the exception of very young recipients with low antibody titres). ABO-incompatible donors for paediatric or adult recipients have been described [25Rydberg L. ABO-incompatibility in solid organ transplantation.Transfus Med. 2001; 11: 325-342Crossref PubMed Scopus (128) Google Scholar, 26Tanabe M. Shimazu M. Wakabayashi G. Hoshino K. Kawachi S. Kadomura T. et al.Intraportal infusion therapy as a novel approach to adult, ABO- incompatible liver transplantation.Transplantation. 2002; 73: 1959-1961Crossref PubMed Google Scholar, 27Egawa H. Uemoto S. Inomata Y. Shapiro A.M. Asonuma K. Kiuchi T. et al.Biliary complications in pediatric living related liver transplantation.Surgery. 1998; 124: 901-910Abstract Full Text Full Text PDF PubMed Google Scholar] but should remain exceptional and have to be evaluated. They should have no history of major abdominal surgery. Most centres accept donors between 18 and 60 years of age. It is apparent that the risk of missing occult medical problems increases with age. Moreover, it has been shown that younger donor age has beneficial effects on early graft function and regenerative capacity of the liver [14Broelsch C.E. Emond J.C. Whitington P.F. Thistlethwaite J.R. Baker A.L. Lichtor J.L. Application of reduced-size liver transplants as split grafts, auxiliary orthotopic grafts, living related segmental transplants.Ann Surg. 1990; 212 (discussion p. 375–376): 368-375Crossref PubMed Google Scholar, 18Kiuchi T. Kasahara M. Uryuhara K. Inomata Y. Uemoto S. Asonuma K. et al.Impact of graft size mismatching on graft prognosis in liver transplantation from living donors.Transplantation. 1999; 67: 321-327Crossref PubMed Scopus (507) Google Scholar, 27Egawa H. Uemoto S. Inomata Y. Shapiro A.M. Asonuma K. Kiuchi T. et al.Biliary complications in pediatric living related liver transplantation.Surgery. 1998; 124: 901-910Abstract Full Text Full Text PDF PubMed Google Scholar, 28Ikegami T. Nishizaki T. Yanaga K. Shimada M. Kishikawa K. Nomoto K. et al.The impact of donor age on living donor liver transplantation.Transplantation. 2000; 70: 1703-1707Crossref PubMed Google Scholar, 29Kawasaki S. Makuuchi M. Matsunami H. Hashikura Y. Ikegami T. Nakazawa Y. et al.Living related liver transplantation in adults.Ann Surg. 1998; 227: 269-274Crossref PubMed Scopus (302) Google Scholar, 30Tanaka K. Uemoto S. Tokunaga Y. Fujita S. Sano K. Nishizawa T. et al.Surgical techniques and innovations in living related liver transplantation.Ann Surg. 1993; 217: 82-91Crossref PubMed Google Scholar, 31Renz J.F. Mudge C.L. Heyman M.B. Tomlanovich S. Kingsford R.P. Moore B.J. et al.Donor selection limits use of living-related liver transplantation.Hepatology. 1995; 22: 1122-1126Crossref PubMed Google Scholar]. Potential donors undergo careful medical investigations, which have three major goals:1.assessment of the medical risk for the donor;2.assessment of the remnant donor liver and suitability of the potential graft for the recipient; and3.psychological assessment of the donor. Investigations routinely performed at most centres for evaluation of the potential donor are listed in Table 2 [14Broelsch C.E. Emond J.C. Whitington P.F. Thistlethwaite J.R. Baker A.L. Lichtor J.L. Application of reduced-size liver transplants as split grafts, auxiliary orthotopic grafts, living related segmental transplants.Ann Surg. 1990; 212 (discussion p. 375–376): 368-375Crossref PubMed Google Scholar, 18Kiuchi T. Kasahara M. Uryuhara K. Inomata Y. Uemoto S. Asonuma K. et al.Impact of graft size mismatching on graft prognosis in liver transplantation from living donors.Transplantation. 1999; 67: 321-327Crossref PubMed Scopus (507) Google Scholar, 23Schiano T.D. Kim-Schluger L. Gondolesi G. Miller C.M. Adult living donor liver transplantation: the hepatologist's perspective.Hepatology. 2001; 33: 3-9Crossref PubMed Scopus (76) Google Scholar, 27Egawa H. Uemoto S. Inomata Y. Shapiro A.M. Asonuma K. Kiuchi T. et al.Biliary complications in pediatric living related liver transplantation.Surgery. 1998; 124: 901-910Abstract Full Text Full Text PDF PubMed Google Scholar, 28Ikegami T. Nishizaki T. Yanaga K. Shimada M. Kishikawa K. Nomoto K. et al.The impact of donor age on living donor liver transplantation.Transplantation. 2000; 70: 1703-1707Crossref PubMed Google Scholar, 29Kawasaki S. Makuuchi M. Matsunami H. Hashikura Y. Ikegami T. Nakazawa Y. et al.Living related liver transplantation in adults.Ann Surg. 1998; 227: 269-274Crossref PubMed Scopus (302) Google Scholar, 30Tanaka K. Uemoto S. Tokunaga Y. Fujita S. Sano K. Nishizawa T. et al.Surgical techniques and innovations in living related liver transplantation.Ann Surg. 1993; 217: 82-91Crossref PubMed Google Scholar, 31Renz J.F. Mudge C.L. Heyman M.B. Tomlanovich S. Kingsford R.P. Moore B.J. et al.Donor selection limits use of living-related liver transplantation.Hepatology. 1995; 22: 1122-1126Crossref PubMed Google Scholar, 32Trotter J.F. Wachs M. Everson G.T. Kam I. Adult-to-adult transplantation of the right hepatic lobe from a living donor.N Engl J Med. 2002; 346: 1074-1082Crossref PubMed Scopus (316) Google Scholar, 33Sterneck M. Nischwitz U. Fischer L. Malago M. Rogiers X. Raedler A. et al.Evaluation and morbidity of the living liver donor in pediatric liver transplantation.Transplant Proc. 1995; 27: 1164-1165PubMed Google Scholar]. One of the most serious potential complications of living donation is the perioperative development of pulmonary embolism. Several cases have been reported in the literature [34Sterneck M. Nischwitz U. Burdelski M. Kjer S. Rogiers X. Broelsch C.E. Selection of live donors for segmental liver transplantation in children.Dtsch Med Wochenschr. 1996; 121: 189-194Crossref PubMed Google Scholar, 35Renz J.F. Busuttil R.W. Adult-to-adult living-donor liver transplantation: a critical analysis.Semin Liver Dis. 2000; 20: 411-424Crossref PubMed Scopus (63) Google Scholar, 36Testa G. Malago M. Nadalin S. Hertl M. Lang H. Frilling A. Right-liver living donor transplantation for decompensated end-stage liver disease.Liver Transpl. 2002; 8: 340-346Crossref PubMed Scopus (59) Google Scholar, 37Durand F. Ettorre G.M. Douard R. Denninger M.H. Kianmanesh A. Sommacale D. et al.Donor safety in living related liver transplantation: underestimation of the risks for deep vein thrombosis and pulmonary embolism.Liver Transpl. 2002; 8: 118-120Crossref PubMed Scopus (34) Google Scholar, 38Jones J. Payne W.D. Matas A.J. The living donor-risks, benefits and related concerns.Transplant Rev. 1993; 7: 115-128Abstract Full Text PDF Google Scholar, 39Anonymous. The international living donor transplantation registry. 1997.Google Scholar]. In one case, the mother who donated for her child even died as a consequence of this complication [[34]Sterneck M. Nischwitz U. Burdelski M. Kjer S. Rogiers X. Broelsch C.E. Selection of live donors for segmental liver transplantation in children.Dtsch Med Wochenschr. 1996; 121: 189-194Crossref PubMed Google Scholar]. Known risk factors for thromboembolic events include obesity, treatment with estrogens, older age, presence of varicose veins, smoking and a family history of thrombosis with an underlying inherited procoagulation disorder. Most centres screen potential donors for the presence of factor V Leiden gene mutations, prothrombin gene mutations, protein C, protein S, AT III deficiency, factor VIII elevation, as well as the presence of antiphospholipid or cardiolipin antibodies. It is a matter of debate whether potential donors with a mildly increased risk for thrombotic events should be excluded from donation. For example, heterozygote carriers of a factor V Leiden gene mutation – present in approximately 3–8% of the European population – have a 3–8 times higher chance of developing thrombosis. However, most centres agree that donors have to stop smoking and taking oral contraceptives or estrogens once the evaluation process starts.Table 2Evaluation protocol for potential living liver donorsa* Only before adult living donor liver transplantation.Step 0:Telephone consultation: relation to recipient, age, weight and size, medical history, ABO compatibilityStep 1Psychologic evaluationClinical evaluation:Medical history and physical examinationLaboratory tests:Erythrocyte sedimentation rate, differential blood count, electrolytes, liver, kidney and pancreas profile, glucose, protein, protein electrophoresis, triglycerides, cholesterol, TSH, C-reactive protein, ferritin, transferrin saturation, alpha-1 antitrypsin level, antinuclear antibody screen, coagulation profile, urianalysisSerology for HBV, HCV, HIV, CMV, EBV, HSV, detailed screening of procoagulation disorders: protein C, protein S antithrombin III, factors V Leiden mutation, prothrombin mutation, homocystein, factor VIII, cardiolipin and anti-phospholipid antibodiesStep 2(Non- or little invasive investigations)ElectrocardiographyStress electrocardiographyChest radiographyPulmonary function testEchocardiography (if age of donor>40)Abdominal ultrasoundUpper abdominal CT-scan with volumetry of the liverStep 3(More invasive or special investigations)MRI of liver, biliary system and hepatic vasculatureDoppler ultrasound of the carotid arteries ( if age of donor>40)Celiac angiography*Liver biopsy*Step 4Final medical evaluationFormal surgical evaluation and consent of the donorPreoperative anesthesia evaluation and consent of the donorPlanning of the surgical date and availability of ICU facilitiesHBV-vaccination, autologous blood donationFinal psychological and ethical evaluationa * Only before adult living donor liver transplantation. Open table in a new tab Suitability of the donor liver as a graft is assessed with regard to quality, size, vascular and biliary anatomy. Obtaining an accurate estimate of liver volume during the donor evaluation is critical to ensure that the right and left lobes contain sufficient liver mass to sustain function in the recipient and donor, respectively. Recent studies have shown that either computed tomography (CT) or magnetic resonance imaging (MRI) are very accurate methods by which liver volume in the donor can be assessed [40Bogetti J.D. Herts B.R. Sands M.J. Carroll J.F. Vogt D.P. Henderson J.M. Accuracy and utility of 3-dimensional computed tomography in evaluating donors for adult living related liver transplants.Liver Transpl. 2001; 7: 687-692Crossref PubMed Scopus (36) Google Scholar, 41Higashiyama H. Yamaguchi T. Mori K. Nakano Y. Yokoyama T. Takeuchi T. et al.Graft size assessment by preoperative computed tomography in living related partial liver transplantation.Br J Surg. 1993; 80: 489-492Crossref PubMed Google Scholar, 42Fulcher A.S. Szucs R.A. Bassignani M.J. Marcos A. Right lobe living donor liver transplantation: preoperative evaluation of the donor with MR imaging.AJR Am J Roentgenol. 2001; 176: 1483-1491Crossref PubMed Google Scholar]. In general, volume of the right lobe estimated by these imaging techniques was within 10–15% of the liver mass determined by weighing the liver after resection. Nowadays many centres prefer to perform volumetric determinations by MRI since anatomical details of the hepatic veins, hepatic arteries, portal vein and bile ducts can be studied using the same procedure. In addition, the risk of allergic reactions to the contrast medium and the radiation exposure are avoided. However, a recent study showed that volumetric measurement together with visualisation of the hepatic arteries, portal veins, hepatic veins and bile ducts can be performed in a single computed CT scan [43Schroeder T. Malago M. Debatin J.F. Testa G. Nadalin S. Broelsch C.E. et al.Multidetector computed tomographic cholangiography in the evaluation of potential living liver donors.Transplantation. 2002; 73: 1972-1973Crossref PubMed Google Scholar, 44Schroeder T. Nadalin S. Stattaus J. Debatin J.F. Malago M. Ruehm S.G. Potential living liver donors: evaluation with an all-in-one protocol with multi-detector row, CT.Radiology. 2002; 224: 586-591Crossref PubMed Google Scholar]. The safety of the donor is a primordial concern in living liver donation. Since, in regular liver resection surgery, a clear relationship between mortality and extent of the resection has been demonstrated [[45]Iwatsuki S. Sheahan D.G. Starzl T.E. The changing face of hepatic resection.Curr Probl Surg. 1989; 26: 281-379Abstract Full Text PDF PubMed Google Scholar], it is to be expected that donors with a smaller residual liver volume will have a higher risk of complications and/or mortality. Both remnant liver volume and liver quality play a role. Remnant liver volume is usually expressed as a percentage of the standard liver volume (SLV). The SLV can be calculated using the Heinemann formula [[46]Heinemann A. Wischhusen F. Puschel K. Rogiers X. Standard liver volume in the Caucasian population.Liver Transpl Surg. 1999; 5: 366-368Crossref PubMed Google Scholar] for Caucasians or the Urata formula [[47]Urata K. Kawasaki S. Matsunami H. Hashikura Y. Ikegami T. Ishizone S. Calculation of child and adult standard liver volume for liver transplantation.Hepatology. 1995; 21: 1317-1321Crossref PubMed Google Scholar] for Asiatic patients. In general, a remnant liver volume of 40% of the SLV or more is regarded to be safe for the donor. However, Fan et al. [[48]Fan S.T. Lo C.M. Liu C.L. Yong B.H. Chan J.K. Ng I.O. Safety of donors in live donor liver transplantation using right lobe grafts.Arch Surg. 2000; 135: 336-340Crossref PubMed Google Scholar] showed that also a residual liver volume of only 30% can be tolerated by the donor if steatosis is not present. Indeed, liver quality, particulary the grade of fatty degeneration is of uppermost importance. Some centres evaluate parenchymal liver changes by CT or MRI appearance. Others will systematically perform liver biopsies. Obtaining an accurate estimate of the liver volume during donor evaluation is critical to ensure that the right and left lobes contain sufficient liver mass to sustain function in both the recipient and donor. In liver resections for liver tumours, extended hepatectomy with a remnant liver volume of 15–20% of SLV can be tolerated in non-cirrhotic patients [[49]Starzl T.E. Putnam C.W. Groth C.G. Corman J.L. Taubman J. Alopecia, ascites, and incomplete regeneration after 85 to 90 per cent liver resection.Am J Surg. 1975; 129: 587-590Abstract Full Text PDF PubMed Google Scholar]. The transplanted volume in LDLT requires periods of cold and warm ischemia, subsequent reperfusion of the graft and immunosuppression. Thus, the minimal graft volume required to meet the metabolic demand of the recipient is undefined till now. There is general agreement that the lower limit depends on the recipient's condition, the quality of the graft as well as the technique of implantation performed. Shirakata et al. [[50]Shirakata Y. Terajima H. Mashima S. Inomoto T. Nishizawa F. Saad S. et al.The minimum graft size for successful orthotopic partial liver transplantation in the canine model.Transplant Proc. 1995; 27: 545-546PubMed Google Scholar] reported that 25% of SLV is approximately the minimum graft size for successful liver transplantation in a canine liver transplantation setting. This critical limit of graft volume was confirmed by Lo et al. in humans. The authors performed successful adult-to-adult LDLT for patients with fulminant hepatic failure (FHF) with a graft volume of only 25% of the SLV [[51]Lo C.M. Fan S.T. Chan J.K. Wei W. Lo R.J. Lai C.L. Minimum graft volume for successful adult-to-adult living donor liver transplantation for fulminant hepatic failure.Transplantation. 1996; 62: 696-698Crossref PubMed Google Scholar]. Nevertheless, they also stated that a graft volume of 40% or less of SLV should be considered as a high-risk graft, with a lower success rate [[52]Lo C.M. Fan S.T. Liu C.L. Chan J.K. Lam B.K. Lau G.K. et al.Minimum graft size for successful living donor liver transplantation.Transplantation. 1999; 68: 1112-1116Crossref PubMed Scopus (178) Google Scholar]. Kawasaki et al. [[29]Kawasaki S. Makuuchi M. Matsunami H. Hashikura Y. Ikegami T. Nakazawa Y. et al.Living related liver transplantation in adults.Ann Surg. 1998; 227: 269-274Crossref PubMed Scopus (302) Google Scholar] reported a 100% graft survival rate and no small-for-size syndrome in 13 recipients of left lobe grafts with a size between 32 and