Analysis of postoperative liver function of donors in living-related liver transplantation: comparison of the type of donor hepatectomy

Pathologic Analysis of Right-Lobe Graft Failure in Adult-to-Adult Live Donor Liver Transplantation

Live donor adult liver transplantation (LDALT) utilizing right-lobe grafts is now acceptable as an alternative to cadaveric orthotopic liver transplantation (OLT). However, some LDALTs fail and require urgent OLT or result in recipient death. Our aim was to determine the basis of LDALT failure. Liver specimens from 49 LDALT recipients were evaluated and the findings correlated with clinical outcome. Ten patients (20.4%) had either early (< 1 month) or late (> 1 month) graft failure. Eight early failures, 7 of which occurred among our first 25 cases, were due to extensive liver parenchymal necrosis as a result of hepatic artery thrombosis (n=3), portal vein thrombosis (n= 1), hyperperfusion syndrome (n= 1), complete graft thrombosis (n= 1) with Factor V Leiden on a regimen of therapeutic heparin (n=1), sepsis and concomitant graft dysfunction with venous outflow tract injury (n=I), and venous outflow tract thrombosis and parenchymal thermal injury with sepsis (n=1). Preoperative, intraoperative, or postoperative severe vessel wall injury was evident in 6/8 early failures. TWo patients had late graft failure, 1 from recurrent hepatitis C and 1 with sepsis/multisystem organ failure. There were no significant differences in graft size, rejection episodes, or operative or ischemic times between patients with and without graft failure. In conclusion, LDALT failed in 10/49 (20%) of our patients, with 8/10 occurring within 1 month post-LDALT owing to vascular/thrombotic complications experienced during the early phase of our institutional experience. Perioperative vessel wall injury appeared to be a major factor in predicting early graft loss.

Management of the middle hepatic vein in right lobe living donor liver transplantation: A meta-analysis

Living donor liver transplantation (LDLT) is a curative treatment for end stage liver disease. It is advantageous due to the shortage of deceased donors. However, in LDLT, whether the middle hepatic vein (MHV) should be preserved in donors remains controversial. We conducted searches in Pubmed, Embase, Cochrane Library, Web of Science, Ovid, and Google Scholar using the key words "living donor liver transplantation" and "middle hepatic vein". Due to ethical issues, there were no randomized control trails focusing on MHV in LDLT. The majority of reports were retrospective studies. We examined the reference lists to identify related investigations. Google Scholar was then used to obtain full texts. Nine observational studies were analyzed. There were no significant differences in liver function (WMD, -5.51; P=0.12) and complications (RR, 0.98; P=0.89) in donors with or without MHV. However, the liver function in recipients was greatly improved after LDLT with MHV (WMD, -78.32; P=0.01). No definite conclusion was obtained in terms of the liver regeneration indices between LDLT with or without MHV. It was conclude that grafts with MHV in LDLT favor recipient outcomes and do not harm the living donor if a careful preoperative evaluation is performed.

Clinical significance of right hepatectomy along the main portal fissure on donors in living donor liver transplantation

There might be discordance between inter-lobar borders of the main portal fissure (MPF) using the middle hepatic vein (MHV) and of the portal segmentation. Forty-five living donors who underwent right hepatectomy for the adult recipients from 2007 to 2011 in a tertiary hospital were retrospectively analyzed. The donors were classified into conventional right hepatectomy along the MPF (cRL group, n = 26) and modified right hepatectomy along right-side shifted transection plane from the MPF (mRL group, n = 19). The cRL donors had higher postoperative peak level of INR (1.84 vs. 1.62; P = 0.022), and bilirubin (3.37 mg/dl vs. 2.74 mg/dl; P = 0.065) than the mRL donors. cRL donors experienced greater depression of platelet count (144 per nL vs. 168 per nL; P = 0.042) and enlargement of splenic volume (52% vs. 37%; P = 0.025) than mRL donors for 7 days after hepatectomy. The regeneration of the left lateral sector was more accelerated in the cRL donors than the mRL donors for postoperative 3 months (148% vs. 84%; P = 0.015). There were no differences in the post-transplant graft function, incidence of complications, and graft survival rates between the two groups of recipients (P > 0.05). This study suggests that the conventional right hepatectomy along the MHV might increase donor risk by reducing parenchymal liver volume of the segment IV.

Matrix metalloproteinase 2 in reduced-size liver transplantation: beyond the matrix

We studied the contribution of matrix metalloproteinase 2 (MMP2) and matrix metalloproteinase 9 (MMP9) to the beneficial effects of preconditioning (PC) in reduced-size orthotopic liver transplantation (ROLT). We also examined the role of c-Jun N-terminal kinase (JNK) and whether it regulates MMP2 in these conditions. Animals were subjected to ROLT with or without PC and pharmacological modulation, and liver tissue samples were then analyzed. We found that MMP2, but notMMP9, is involved in the beneficial effects of PC in ROLT. MMP2 reduced hepatic injury and enhanced liver regeneration. Moreover, inhibition of MMP2 in PC reduced animal survival after transplantation. JNK inhibition in the PC group decreased hepatic injury and enhanced liver regeneration. Furthermore, JNK upregulated MMP2 in PC. In addition, we showed that Tissue inhibitors of matrix metalloproteinases 2 (TIMP2) was also upregulated in PC and that JNK modulation also altered its levels in ROLT and PC. Our results open up new possibilities for therapeutic treatments to reduce I/R injury and increase liver regeneration after ROLT, which are the main limitations in living-donor transplantation.

Effect of angiotensin II and bradykinin inhibition in rat reduced-size liver transplantation

This study examined whether angiotensin II (Ang II) blockers [Ang II type I receptor antagonist, Ang II type II receptor antagonist, and angiotensin converting enzyme (ACE) inhibitor] could reduce hepatic injury and improve regeneration in reduced-size orthotopic liver transplantation (ROLT) and whether the beneficial effects of ischemic preconditioning (PC) in ROLT could be explained by changes in Ang II. We show that small liver grafts generated Ang II after ROLT and that this was associated with increased angiotensinogen and ACE messenger RNA expression. Furthermore, inhibition of Ang II did not contribute to PC-induced protection in ROLT. All Ang II blockers reduced hepatic injury, but none of them promoted liver regeneration. Bradykinin (BK) receptor antagonist improved liver regeneration but did not reduce hepatic injury in ROLT. Finally, the combination of Ang II blockers and BK receptor antagonists in ROLT reduced hepatic injury and improved liver regeneration. In conclusion, treatments with either Ang II blockers or BK receptor antagonists cannot, on their own, improve the outcome of ROLT. Although Ang II blockers can reduce hepatic ischemia-reperfusion injury and BK receptor antagonists can promote liver regeneration, neither confers both benefits at the same time. Consequently, it may be of clinical interest to apply both treatments simultaneously.

Preoperative Helical Computerized Tomography Estimation of Donor Liver Volume

BACKGROUND

The purpose of this study was to evaluate the accuracy of spiral computed tomography (CT) and 3-D imaging models in measuring total and segmental liver volume in potential living donors.

METHODS

A prospective study was undertaken to assess the correlation between the volumes of potential donor livers determined via helical CT and the actual volumes measured during operation in 150 donor candidates. Left-lateral segment (S2,3) or left-lobe (S2,3,4) transplantation was performed in 36 cases with 96 right-lobe liver transplants (S5,6,7,8). Ten donor candidates were refused owing to inadequate liver volumes, and 8 for other reasons.

RESULTS

The regression analysis model showed a significant correlation between the preoperative CT estimates of graft volume and intraoperative weight measurement of harvested grafts in living liver donors (F: 5525.37; P < .05); 97.7% of changes in CT volume were explained by differences in graft mass (R2: 0.977).

CONCLUSION

Preoperative estimation of segmental volumes of the donor liver is necessary to avoid donor-recipient size disparity, thereby preventing hepatic failure of donors after harvesting. It has a major impact on donor selection and type of surgical management. The accuracy of helical CT was high to determine total and segmental liver volumes.

Differences of perioperative liver function, transfusion, and complications according to the type of hepatectomy in living donors

Numerous living donor hepatectomy are being performed safely. However, donors are still exposed to various complications including hepatic failure. We examined the donor's potential risk and morbidity depending on the type of hepatectomy: left lateral segmentectomy (group LLS, n = 30), left lobectomy (group LL, n = 15), and right lobectomy (group RL, n = 128). The charts and computerized hospital data of 173 donors from March 2000 to September 2003 were retrospectively reviewed. We analyzed liver function tests (LFT), RBC transfusion, and complications. Although the graft weight was greatest, and surgical and anesthetic times were longest in the group RL, there were no significant differences in postoperative hospital stay, RBC transfusion, and major complications among the groups. However, minor complications were significantly higher in group RL than group LLS. Postoperative prothrombin time and total bilirubin were significantly higher in the group RL than the other groups (P < 0.05). Living donor hepatectomy is relatively safe, and it is evidenced by rapid recovery of LFT and low occurrence of major complications. However, noticeable depression of LFT and frequent minor complications occur after hepatectomy, especially RL.

Protection of reduced-size liver for transplantation

The shortage of available organs for liver transplantation has motivated the development of new surgical techniques such as reduced-size liver transplantation. Ischemia-reperfusion (I/R) associated with liver transplantation impairs liver regeneration. Ischemic preconditioning is effective against I/R injury in clinical practice of liver tumour resections. The present study evaluated the effect of ischemic preconditioning on reduced-size liver for transplantation and attempted to identify the underlying protective mechanisms. Hepatic injury and regeneration (transaminases, proliferating cell nuclear antigen [PCNA] labeling index, and hepatocyte growth factor [HGF]) were assessed after reduced-size orthotopic liver transplantation (ROLT). Energy metabolism, oxidative stress, tumor necrosis factor-alpha (TNF) and interleukin-6 (IL-6) were examined as possible mechanisms involved in liver regeneration. Ischemic preconditioning reduced transaminase levels and increased HGF levels and the percentage of PCNA-positive hepatocytes after ROLT. This was associated with a decrease in oxidative stress following ROLT, whereas energy metabolism and hepatic IL-6 and TNF release were unchanged. The benefits of ischemic preconditioning on hepatic injury and liver regeneration could be mediated, at least partially by nitric oxide. These results suggest a new potential application of ischemic preconditioning in reduced-size liver transplantation.

Adult-to-adult living donor liver transplant: UK experience

BACKGROUND

Adult-to-adult living donor liver transplantation (ALDLT) is being adopted widely in the USA and mainland Europe, fueled by the increasing waiting lists for cadaver organs. The present report describes the first UK experience with the procedure in patients from overseas who have the lowest priority for cadaver organ allocation.

METHODS

The 16 patients seen over the period November 1998 to March 2002 had end-stage cirrhosis from chronic hepatitis C virus (HCV) or hepatitis B virus (HBV) infection (13 cases), with single instances of cryptogenic cirrhosis, secondary biliary cirrhosis and alcoholic liver disease. Grafts were left lobe in the first two recipients and right lobe in the subsequent 14 recipients, donated by nine sons/daughters and seven brothers/sisters.

RESULTS

Twelve of the 16 recipients did well. The four recipients who died had recurrent sepsis; two of these died following hepatic arterial occlusion, and in three major surgical factors were present before transplantation. Serial computed tomography (CT) measurements in the survivors showed regeneration of the grafted lobe with final volumes reaching in each case the calculated standard liver volume for body size. In the donors, liver function tests had returned to normal by day 7-14, with rapid regeneration of the remaining lobe, although the final size attained that estimated before donation in only four donors.

CONCLUSIONS

ALDLT, although requiring considerable facilities and organization, can give good results for both recipient and donor. As with cadaver grafts, outcome in the recipient if the larger right lobe is used is dependent on surgical risk factors and the severity of clinical decompensation before transplantation. Measures to ensure the safety of the donors remain the main concern.

Donor health assessment after living-donor liver transplantation

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Partial liver transplantation

Since the introduction of the split-liver transplantation procedure 15 years ago a variety of partial liver transplantations have been developed. The earliest form of split-liver transplantation consisted of reduction of a whole liver graft to just the left lateral segment or the left liver lobe, which was then small enough to transplant to a young child. The rest of the liver was discarded. This method partially solved the great need for liver grafts for children but as the remaining part of the liver was discarded the method was in fact detrimental for adults on the waiting list. Further surgical development resulted in splitting of the liver ex vivo into two transplantable partial grafts: the left part to a child and the right lobe to an adult. This procedure was successfully introduced but the complicated logistics resulted in prolonged cold ischemia times for the grafts. In order to keep the cold ischemia time as short as possible, the in situ split-liver technique was developed, in which the liver was split in the post-mortem donor. Refinement of this operation led to results which were superior to those obtained with the ex vivo method; moreover, it opened the door to living-donor liver transplantation. The first successful procedure was performed from a mother to a child, who received the mother's left liver segment. The introduction of this technique resulted over the years in a decrease in the pediatric waiting list to almost zero. As the demand for organs increases every year and the number of donors remains constant in Western countries, the right-lobe living-donor liver transplantation for adults has been introduced. Introduction of all forms of partial liver transplantation has relieved the pressure on waiting lists, especially for children but also for adults. There are, however, serious concerns regarding the high morbidity and mortality rates associated with the living-donor donation procedure.

Living donor liver transplantation: summary of a conference at The National Institutes of Health

Living donor liver transplantation for adults was developed only recently in an attempt to increase the pool of donor organs; to reduce morbidity and mortality; and to improve the long-term survival of patients in need of liver transplant. Within a few brief years, this procedure has gained widespread support by both the public and transplant community. The procedure will soon be performed by nearly 80% of all liver transplant programs in the United States. Unfortunately, the long-term risks of the procedure to the recipient and especially the donor remain undefined. In response to the rapid growth and enthusiasm for this procedure, the National Institutes of Health sponsored a workshop, the goals of which were to review the scientific, medical, and nonmedical issues associated with living donor liver transplantation, and to define questions for future basic and clinical investigations which could improve the success and applicability of this procedure.

Safe donor hepatectomy for living related liver transplantation

Minimizing the risk of donor hepatectomy while preserving graft viability is an important concern in living related liver transplantation. This report describes clinical outcomes for living donor hepatectomy with reference to the type of hepatectomy. Donor hepatectomy was performed in 130 consecutive living donors. They were divided into three groups: left lateral or extended left lateral segmentectomy (group S; n = 50), left hepatectomy with or without caudate lobe or right lateral resection (group L; n = 64), and right hepatectomy (group R; n = 16). Intraoperative and postoperative data were examined and compared among the groups. No critical complications were observed in any group. However, there were differences in donor age, surgical and ischemia times, volume of blood loss, graft weight, and aspartate aminotransferase level elevation among the groups. Livers showed a substantial increase in volume, tending to the standard liver volume 1 month after surgery. Regardless of the extent of donor hepatectomy, serious complications did not occur after surgery. Surgical risk for a living donor is minimal if the operation is performed by experienced surgeons using present procedures.

Adult living donor liver transplantation: current status

Living donor liver transplantation was developed in response to a shortage of full-size grafts for children. The progression from reduced-size cadaveric grafts to use of living donors occurred subsequent to expansion of liver anatomy knowledge and practical use of hepatic segments. A major benefit of pediatric live donor liver transplantation is the grafting of children without using livers from the cadaver donor pool. A major drawback of the procedure relates to the need to perform surgery and assign risk to an otherwise healthy individual. The ethical challenge has been discussed in detail and, although not ideal, the procedure "passes muster" on grounds of informed consent and the good of helping another human being. Formidable success appears to have been attained with the adult-to-adult procedure thus far; however, the transplant community still awaits center-specific and compiled data to determine whether the procedure truly reduces adult waiting list times for liver transplant recipients with minimal donor risk.

Liver transplantation. Living donor, hepatocyte, and xenotransplantation

Liver transplantation is now accepted as effective therapy in the treatment of acute and chronic hepatic failure. Improvements in surgical techniques and immune suppression have led to 5-year survival rates that exceed 70% in most centers. The success of transplantation has led to a dramatic increase in the number of candidates to over 14,000 places on the national waiting list. While the number of patients in need of transplantation increases, there has been little growth in the supply of available cadaveric organs, resulting in an organ shortage crisis. With waiting times often exceeding 1 to 2 years, the waiting list mortality now exceeds 10% in most regions. Several novel approaches have been developed to address the growing disparity between the limited supply and excessive demand for suitable organs.

Adult-to-adult living donor liver transplantation

Adult-to-adult living donor liver transplantation has become the subject of a great deal of attention over the last few years. Until the use of the donor right lobe was introduced and demonstrated to be relatively safe, it was not possible to offer this alternative to conventional transplantation to most adults. Recent clinical work has focused on the results of these procedures in both donors and recipients, perfecting surgical techniques for right-lobe transplantation, streamlining donor evaluation protocols, and containing costs. This overview summarizes many of the recent publications and presentations in the field of adult-to-adult living donor liver transplantation.

Long-term complications of living donor liver transplantation

1. Donor outcome after living donor liver transplantation (LDLT) is related to type of liver resection. Left lateral segmentectomy is used in pediatric cases and right lobectomy is used in adult cases. 2. Biliary complications occur in 5% to 10% of both pediatric and adult cases. 3. Three donors, 2 in pediatric LDLT and 1 in adult LDLT, have died. Estimated mortality is 0.13% for pediatric donation and 0.2% for adult donation. 4. Postoperative cholestasis occurs commonly in donors, but clinically relevant jaundice occurs in less than 5%. 5. Other donor morbidity may be related to incisional hernias, postoperative gastric dysfunction, and pain. 6. Donors report overall satisfaction with LDLT, and 88% believed that the role of LDLT should be increased. 7. All donors returned to predonation activities; 25% by 1 month, 75% by 3 months, 88% by 6 months, and 100% by 1 year.

Minimal blood loss living donor hepatectomy

BACKGROUND

Donor hepatectomy with maximal safety while preserving graft viability is of principal concern in living donor liver transplantation. There are compelling reasons for avoiding blood transfusion, even with autologous blood, to avoid the potential risks it imposes on healthy donors. This study aims to describe the surgical technique and clinical outcomes of living donor hepatectomy with minimal blood loss requiring no blood transfusion.

METHODS

Donor hepatectomy was performed in 30 living donors according to a detailed preoperative imaging study of the vascular and biliary anatomy. Liver parenchymal transection was carried out with strict adherence to a meticulous surgical technique without vascular inflow occlusion to either side of the liver. Pre-, intra-, and postoperative data were gathered, and factors related to blood loss were analyzed retrospectively.

RESULTS

The intraoperative blood loss ranged from 20 to 300 ml with a mean of 72.0+/-58.9 ml (median, 55 ml), and neither homologous nor autologous blood transfusion was required in any of the donors intra- and postoperatively. All 30 donors were discharged with minimal complications, and remain well at a mean follow-up of 24 months after donation. Excellent graft viability was verified by the fact that all 30 recipients are alive and well with a few manageable complications. The actual graft and patient survival are both 100% at the time of writing.

CONCLUSIONS

Regardless of the extent of donor hepatectomy, blood loss can and should be kept to a minimum, and living donor hepatectomy without blood transfusion is a realistic objective.

In situ split liver transplantation for two adult recipients

BACKGROUND

Modifications of the in situ split liver technique are needed for safe transplantation in two adult recipients with a single donor.

METHODS

The graft from a brain-dead donor, 187 cm tall and weighing 89 kg, was split in situ with a transection performed along the main portal fissure retaining the middle hepatic vein with the left graft. The right and left grafts, which weighed 985 and 760 g, respectively, were transplanted in two adult recipients weighing 70 and 56 kg, respectively.

RESULTS

Both recipients had minor intraoperative blood loss and were discharged from intensive care on day 3. Both grafts were rapidly functional, and the two patients were in excellent condition with normal liver function tests 9 months after surgery.

CONCLUSION

In situ split liver transplantation can be performed with the middle hepatic vein retained in the left graft to obtain a sufficient volume of the two grafts suitable for two adult recipients. This modification of the technique could expand the donor pool for adult recipients.

Right lobe living donor liver transplantation: a review

The continuing shortage of organs for adult transplant recipients has generated enthusiasm for adult-to-adult living donor liver transplantation (LDLT). The major concern has been the ability to resect a graft of adequate size without subjecting the donor to undue risk. The right hepatic lobe is generally large enough for adult recipients, but because of the real and perceived risks of right lobe (RL) resection, surgeons have been hesitant to offer this option to their patients. The first series of RL resections that included a significant number of patients was reported in 1999, and the results were encouraging. Only minor complications occurred in donors, and the recipients fared quite well. Enthusiasm for these donor resections is growing, and more centers are beginning to perform them. There is a good deal of global experience with pediatric LDLT but little with adults, and there are unique considerations in this population. This review examines donor selection criteria for adult recipients, highlights technical points critical for good outcome, and examines the early results and complications in both donors and recipients. If the preliminary results continue to be reproduced, RL LDLT could have significant impact on the worsening organ shortage.

Acute liver failure

Severe hepatitis A infection is an infrequent but well-recognized cause of acute liver failure that can now be effectively prevented with vaccination against hepatitis A virus. Bromfenac and troglitazone hepatotoxicity as well as various herbal remedies are some of the newly identified causes of acute liver failure. The recently identified transfusion-transmitted virus has been implicated in some cases of idiopathic acute liver failure whereas hepatitis G virus does not appear to be a causative agent. Recognizing, monitoring, and treating patients with life-threatening cerebral edema remain critically important but difficult aspects of the clinical care of acute liver failure. Hypothermia and N-acetylcysteine are promising experimental approaches to cerebral edema but emergency liver transplantation is the only proven means of improving patient survival. Although recent changes in organ allocation may reduce waiting time to transplantation, more reliable and validated markers of liver regeneration and prognosis are needed to triage patients. The potential application and limitations of novel technologies including bioartificial liver devices and auxiliary liver transplantation continue to evolve from pioneering work in animal models and human subjects.

Liver transplantation

The growing disparity between available organs for liver transplantation and the number of waiting recipients has prompted significant debate over organ allocation and distribution. In light of this debate, recipient selection and prediction of factors relating to outcome have become increasingly important. Current immunosuppressive regimens provide excellent short-and long-term survival for patients and grafts. Increasingly, efforts are being made to decrease or withdraw immunosuppression late after transplantation to minimize long-term side effects. Viral disease, particularly cytomegalovirus infection, results in significant morbidity and mortality in patients. However, strategies for targeting high-risk patients with prophylactic antiviral therapy have been successful in reducing the incidence of cytomegalovirus disease. Recurrent viral hepatitis following liver transplantation may limit long-term graft success. Lamivudine appears to limit recurrent infection with hepatitis B virus in a significant number of patients who develop this condition following liver transplantation and may represent a cost savings over hepatitis B immunoglobulin. Although the overall survival of patients with chronic hepatitis C virus infection after orthotopic liver transplantation is excellent, significant morbidity and mortality occur in the subset of patients with severe recurrent disease. Interferon may delay the onset of disease in patients infected with hepatitis C virus following orthotopic liver transplantation, and investigation continues into antiviral therapy in this group of patients.