A new technique of hepatic vein reconstruction in partial liver transplantation

Echinococcosis: Advances in the 21st Century

Echinococcosis is a zoonosis caused by cestodes of the genus Echinococcus (family Taeniidae). This serious and near-cosmopolitan disease continues to be a significant public health issue, with western China being the area of highest endemicity for both the cystic (CE) and alveolar (AE) forms of echinococcosis. Considerable advances have been made in the 21st century on the genetics, genomics, and molecular epidemiology of the causative parasites, on diagnostic tools, and on treatment techniques and control strategies, including the development and deployment of vaccines. In terms of surgery, new procedures have superseded traditional techniques, and total cystectomy in CE, ex vivo resection with autotransplantation in AE, and percutaneous and perendoscopic procedures in both diseases have improved treatment efficacy and the quality of life of patients. In this review, we summarize recent progress on the biology, epidemiology, diagnosis, management, control, and prevention of CE and AE. Currently there is no alternative drug to albendazole to treat echinococcosis, and new compounds are required urgently. Recently acquired genomic and proteomic information can provide a platform for improving diagnosis and for finding new drug and vaccine targets, with direct impact in the future on the control of echinococcosis, which continues to be a global challenge.

Graft loss after pediatric liver transplantation

OBJECTIVE

To describe the epidemiology and causes of graft loss after pediatric liver transplantation and to identify risk factors.

SUMMARY BACKGROUND DATA

Graft failure after transplantation remains an important problem. It results in patient death or retransplantation, resulting in lower survival rates.

METHODS

A series of 157 transplantations in 120 children was analyzed. Graft loss was categorized as early (within 1 month) and late (after 1 month). Risk factors were identified by analyzing recipient, donor, and transplantation variables.

RESULTS

Kaplan-Meier 1-month and 1-, 3-, and 5-year patient survival rates were 85%, 82%, 77%, and 71%, respectively. Graft survival rates were 71%, 64%, 59%, and 53%, respectively. Seventy-one of 157 grafts (45%) were lost: 18 (25%) by death of patients with functioning grafts and 53 (75%) by graft-related complications. Forty-five grafts (63%) were lost early after transplantation. Main causes of early loss were vascular complications, primary nonfunction, and patient death. Main cause of late graft loss was fibrosis/cirrhosis, mainly as a result of biliary complications or unknown causes. Child-Pugh score, anhepatic phase, and urgent transplantation were risk factors for early loss. Donor age, donor/recipient weight ratio, blood loss, and technical-variant liver grafts were risk factors for late loss.

CONCLUSIONS

To prevent graft loss after pediatric liver transplantation, potential recipients should be referred early so they can be transplanted in an earlier phase of their disease. Technical-variant liver grafts are risk factors for graft survival. The logistics of the operation need to be optimized to minimize the length of the anhepatic phase.

Cavocaval liver transplantation without venovenous bypass and without temporary portocaval shunting: the ideal technique for adult liver grafting?

The influence of the implantation technique on the outcome was studied prospectively in a series of 116 consecutive adult patients undergoing primary liver transplantation during the period January 1991-June 1994. Thirty-eight patients (32.8%; group 1) underwent classical orthotopic liver transplantation (OLT) with replacement of the recipient's inferior vena cava (R-IVC) and with venovenous bypass (VVB). Thirty-nine patients (33.56%) had a piggy-back OLT with preservation of the R-IVC (group 2); bypass was used in 17 of them (43.6%) because of poor hemodynamic tolerance of R-IVC occlusion. Thirty-nine patients (33.6%) had OLT without VVB and with side-to-side cavocaval anastomosis (group 3). The three techniques were performed irrespective of the anatomical situation and of the status of the recipient at the time of transplantation. The following parameters were assessed in all patients: implantation time, blood product use, morbidity (e.g., hemorrhagic, thoracic, gastrointestinal, neurological, and renal complications), and outcome. Thirty-one patients underwent detailed intraoperative hemodynamic assessment. The early (< 3 months) post-transplant mortality of 10.3% (12/116 patients) was unrelated to the implantation technique. Group 3 had a significantly shorter mean implantation time, a reduced need for intraoperative blood products, and a lower rate of reoperation due to intra-abdominal bleeding. After excluding two immediate perioperative deaths and eight patients requiring early retransplantation because of primary nonfunction, the frequency of immediate extubation was significantly higher in group 3. Detailed hemodynamic assessment did not show a difference between 6 group 1 patients and 17 group 3 patients, indicating that partial lateral clamping of the IVC fulfills the function of venous bypass. Similar results were obtained in 6 group 2 patients who did not have IVC occlusion. Cavocaval OLT has become our preferred method of liver implantation. It allows the transplantation to be performed without VVB, regardless of the anatomical situation and of the condition of the patient at the time of transplantation. Moreover, it avoids all of the potential complications and costs of VVB.

Liver transplantation in children

Liver transplantation has become the curative surgical therapy of end-stage acute, chronic and metabolic liver disease. This has been made possible by improvements in surgical techniques, such as segmental liver transplantation and by improvements in liver preservation. In parallel, advances in immunosuppression and anti-infective therapy have been achieved. As a result of this progress there is an increasing demand for liver transplantation which raises questions for ethical and socioeconomic consideration.

Total hepatectomy and liver transplantation as two-stage procedure

OBJECTIVE

This article describes the experience with a bridging procedure for a prolonged anhepatic period during clinical liver transplantation in case of special emergency situations.

SUMMARY BACKGROUND DATA

Hepatic necrosis due to fulminant hepatitis or acute graft failure, as well as severe liver trauma are well-known and accepted indications for urgent liver transplantation. Prerequisite is the allocation of a suitable donor organ. If no allograft is available in time, patients with "toxic liver syndrome" or exsanguinating hemorrhage have been shown to benefit from advanced total hepatectomy.

METHODS

As a modification of the standard one-stage procedure, recipient hepatectomy and subsequent liver transplantation are performed in two separate operations. To bridge the prolonged anhepatic period and to allow decompression and return of venous blood, an end-to-side portocaval shunt is constructed temporarily.

RESULTS

Thirteen of thirty-two patients underwent hepatectomy but not transplantation subsequently, and died within 34 hours after progressive deterioration. In 19 of 32 patients, transplantation was realized 6-41 hours after hepatectomy; 9 of 19 patients died, mostly from sepsis. Ten of nineteen liver recipients survived the procedure including three unrelated late deaths; presently, seven patients are alive with a follow-up of 3 to 46 months.

CONCLUSIONS

Two-stage total hepatectomy with temporary portocaval shunt, and subsequent liver transplantation can be a life-saving approach in patients most likely to die of the sequelae of advanced liver or graft necrosis or exsanguination that cannot be controlled by conventional treatment or immediate liver transplantation.

Treatment of inherited metabolic disorders by liver transplantation

Among the worldwide accepted indications for liver transplantation, inherited metabolic disorders play an increasing role. In some paediatric centres this indication runs second after extrahepatic biliary atresia. The aim of liver transplantation in inherited metabolic disorders is twofold: the first is to save a patient's life, the second is to accomplish phenotypic and functional cure of his disease. These aims may be achieved in disorders presenting with cirrhosis, hepatoma, life-threatening progression or failure of other organs with preserved liver function. The timing of liver transplantation has become easier with development of surgical techniques of reduced-size donor livers. These techniques enable the performance of liver transplantation with ABO blood group compatible organs of almost any size if indicated either by deterioration of liver function or impending complications such as hepatoma or life-threatening progression. In comparison with other indications such as extrahepatic biliary atresia, postnecrotic liver cirrhosis or acute liver failure, the results of transplantation in patients with inherited metabolic disorders seem to be better, reaching up to 78-95% actuarial 1-year survival rates. However, lifelong immunosuppressive therapy is necessary. This seems to be acceptable even in disorders with only partial liver function defects.

Application of reduced-size liver transplants as split grafts, auxiliary orthotopic grafts, and living related segmental transplants

The University of Chicago program in pediatric liver transplantation continues actively to seek innovative surgical solutions to problems related to the management of children with end-stage liver disease. Among the most important problems facing these children is a shortage of donor organs, which results from three factors in addition to the actual supply of pediatric donors: the concentration of pediatric liver disease in the population younger than 2 years; the necessity for a graft that is small enough; and the epidemiology of accidents and other events that lead to organ donation. Transplantation using a liver lobe as a graft overcomes size disparity and shifts the available supply of organs from older donors to younger recipients. This work describes the technical aspects of recent innovations in the use of liver lobes in pediatric transplantation, simple reduced-size liver transplantation (RLT), split-liver transplantation (SLT), orthotopic auxiliary liver grafting (ALT), and transplantation using a living related donor (LRLT), and compares their results. Since November 1986 a total of 61 procedures have been performed in which a liver lobe was used as a graft: 26 RLT; 30 SLT, 25 in children and 5 in adults; 5 LRLT; and 1 ALT. Overall 62% of transplants performed in children have involved using a liver lobe as a graft. The rates of complications are somewhat higher than with whole-liver transplantation, but this may not be entirely the result of the complex procedures. Split liver transplantation is associated with the highest mortality and complication rates. Living related liver transplantation has been associated with complications in donors and recipients, but to date survival is 100%. Orthotopic auxiliary liver transplantation effectively corrected the metabolic defect in one patient with ornithine transcarbamylase deficiency. Overall the various modalities of using graft reduction have resulted in postoperative results similar to those achieved with full-size grafts, while pretransplantation mortality has been limited to less than 2%. Thus the use of grafts as liver lobes accomplishes the goal of reducing global mortality among children with end-stage liver disease, but at the cost of increased surgical complexity and more postoperative complications.

Application of reduced-size liver transplants as split grafts, auxiliary orthotopic grafts, and living related segmental transplants

The University of Chicago program in pediatric liver transplantation continues actively to seek innovative surgical solutions to problems related to the management of children with end-stage liver disease. Among the most important problems facing these children is a shortage of donor organs, which results from three factors in addition to the actual supply of pediatric donors: the concentration of pediatric liver disease in the population younger than 2 years; the necessity for a graft that is small enough; and the epidemiology of accidents and other events that lead to organ donation. Transplantation using a liver lobe as a graft overcomes size disparity and shifts the available supply of organs from older donors to younger recipients. This work describes the technical aspects of recent innovations in the use of liver lobes in pediatric transplantation, simple reduced-size liver transplantation (RLT), split-liver transplantation (SLT), orthotopic auxiliary liver grafting (ALT), and transplantation using a living related donor (LRLT), and compares their results. Since November 1986 a total of 61 procedures have been performed in which a liver lobe was used as a graft: 26 RLT; 30 SLT, 25 in children and 5 in adults; 5 LRLT; and 1 ALT. Overall 62% of transplants performed in children have involved using a liver lobe as a graft. The rates of complications are somewhat higher than with whole-liver transplantation, but this may not be entirely the result of the complex procedures. Split liver transplantation is associated with the highest mortality and complication rates. Living related liver transplantation has been associated with complications in donors and recipients, but to date survival is 100%. Orthotopic auxiliary liver transplantation effectively corrected the metabolic defect in one patient with ornithine transcarbamylase deficiency. Overall the various modalities of using graft reduction have resulted in postoperative results similar to those achieved with full-size grafts, while pretransplantation mortality has been limited to less than 2%. Thus the use of grafts as liver lobes accomplishes the goal of reducing global mortality among children with end-stage liver disease, but at the cost of increased surgical complexity and more postoperative complications.

Transplantation of two patients with one liver. Analysis of a preliminary experience with 'split-liver' grafting

Surgical reduction of donor livers to treat small children has been performed successfully in several centers. While this procedure improves the allocation of livers, it does not increase the organ supply. We have extended reduced-size orthotopic liver transplantation (OLT) to treat 18 patients with 9 livers, accounting for 26% of our transplants during a 10-month period and have evaluated the results. In 18 split liver OLTs, patient survival was 67% and graft survival was 50%. In comparison, for 34 patients treated with full-size OLT during the same period, patient survival was 84% (p = 0.298) and graft survival was 76% (p = 0.126). Biliary complications were significantly more frequent in split grafts, occurring in 27%, as compared to 4% in full-sized grafts (p = 0.017). Primary nonfunction (4% versus 5.5%) and arterial thrombosis (6% versus 9%) occurred with similar frequency in split and full-size OLT (p = not significant). These results demonstrated that split-liver OLT is feasible and could have a substantial impact in transplant practice. We believe that biliary complications can be prevented by technical improvements and that split-liver OLT will improve transplant therapy by making more livers available.

Transplantation of two patients with one liver. Analysis of a preliminary experience with 'split-liver' grafting

Surgical reduction of donor livers to treat small children has been performed successfully in several centers. While this procedure improves the allocation of livers, it does not increase the organ supply. We have extended reduced-size orthotopic liver transplantation (OLT) to treat 18 patients with 9 livers, accounting for 26% of our transplants during a 10-month period and have evaluated the results. In 18 split liver OLTs, patient survival was 67% and graft survival was 50%. In comparison, for 34 patients treated with full-size OLT during the same period, patient survival was 84% (p = 0.298) and graft survival was 76% (p = 0.126). Biliary complications were significantly more frequent in split grafts, occurring in 27%, as compared to 4% in full-sized grafts (p = 0.017). Primary nonfunction (4% versus 5.5%) and arterial thrombosis (6% versus 9%) occurred with similar frequency in split and full-size OLT (p = not significant). These results demonstrated that split-liver OLT is feasible and could have a substantial impact in transplant practice. We believe that biliary complications can be prevented by technical improvements and that split-liver OLT will improve transplant therapy by making more livers available.

Transplantation of two patients with one liver. Analysis of a preliminary experience with 'split-liver' grafting

Surgical reduction of donor livers to treat small children has been performed successfully in several centers. While this procedure improves the allocation of livers, it does not increase the organ supply. We have extended reduced-size orthotopic liver transplantation (OLT) to treat 18 patients with 9 livers, accounting for 26% of our transplants during a 10-month period and have evaluated the results. In 18 split liver OLTs, patient survival was 67% and graft survival was 50%. In comparison, for 34 patients treated with full-size OLT during the same period, patient survival was 84% (p = 0.298) and graft survival was 76% (p = 0.126). Biliary complications were significantly more frequent in split grafts, occurring in 27%, as compared to 4% in full-sized grafts (p = 0.017). Primary nonfunction (4% versus 5.5%) and arterial thrombosis (6% versus 9%) occurred with similar frequency in split and full-size OLT (p = not significant). These results demonstrated that split-liver OLT is feasible and could have a substantial impact in transplant practice. We believe that biliary complications can be prevented by technical improvements and that split-liver OLT will improve transplant therapy by making more livers available.

Size reduction of the donor liver is a safe way to alleviate the shortage of size-matched organs in pediatric liver transplantation

The development of pediatric liver transplantation is considerably hampered by the dire shortage of small donor organs. This is a very sad situation because in most experienced centers, liver replacement can offer a long-term hope of survival of more than 70% in a growing variety of pediatric liver disorders. The reported experience with 54 reduced-size grafts on a total of 141 transplants performed in 117 children between 1984 and 1988 demonstrates that the technique of reduced-size liver transplantation not only allows long-term survival but, in fact, offers the same survival hope with the same quality of liver function, regardless of the child's age and clinical condition. The prominent feature of our experience with the reduced liver concerns its deliberate use for elective cases. Seventy-seven per cent of the 30 children who electively received a reduced liver were alive 1 year after transplantation, as were 85% of the 62 children who received a full-size graft. There is no difference in the long-term survival rate of patients who received elective grafts, which is in the range of 75% with both techniques.

Liver transplantation (1)

Advances in the management of both chronic and acute hepatic disease have been made possible and even mandated by the development of liver transplantation. The clinical use of transplantation has proceeded at a rapid pace since a Consensus Development Conference of the National Institutes of Health concluded in June 1983 that liver transplantation had become a service and not simply an experimental procedure.1

The liver can be transplanted as an extra (auxiliary) organ at an ectopic site, or in the orthotopic location after the removal of the host liver (Fig. 1 ). This article will focus primarily on the orthotopic procedure. However, there has been renewed interest in the auxiliary operation, which will be discussed separately.