Is it right to develop living related liver transplantation? Do reduced and split livers not suffice to cover the needs?

Pediatric liver transplantation

In previous decades, pediatric liver transplantation has become a state-of-the-art operation with excellent success and limited mortality. Graft and patient survival have continued to improve as a result of improvements in medical, surgical and anesthetic management, organ availability, immunosuppression, and identification and treatment of postoperative complications. The utilization of split-liver grafts and living-related donors has provided more organs for pediatric patients. Newer immunosuppression regimens, including induction therapy, have had a significant impact on graft and patient survival. Future developments of pediatric liver transplantation will deal with long-term follow-up, with prevention of immunosuppression-related complications and promotion of as normal growth as possible. This review describes the state-of-the-art in pediatric liver transplantation.

Results of split liver transplantation in children

OBJECTIVE

To analyze the outcome of 80 consecutive pediatric split liver transplants performed at the authors' center between 1994 and 2000.

SUMMARY BACKGROUND DATA

Split liver transplantation has become an accepted method of increasing the number of available grafts for pediatric liver transplant recipients.

METHODS

The age of the patients at the time of transplantation ranged from 5 days to 16 years (median 3 years). Sixteen transplants were performed for acute liver failure and 64 for chronic liver failure. The ex situ splitting technique was used for all but four grafts. Fourteen livers were split for two pediatric recipients. Posttransplant follow-up ranged from 6 to 84 months (median 42 months).

RESULTS

Overall patient survival at 6 months follow-up was 96.2%. Graft survival at six months was 93.7%. The Kaplan-Meier patient survival rates at 1 and 3 years were 93.5% and 88.1%, and the graft survival rates were 89.7% and 86.1%, respectively. Four patients required retransplantation. In the acute group (n = 16), the patient survival rates were 93.7% at 1 year and 76.4% at 3 years; there were three deaths due to posttransplant lymphoproliferative disease (PTLD), sepsis, and chronic rejection. In the chronic group (n = 64), the 1- and 3-year patient survival rates were 93.6% and 90.9%, respectively. There were six deaths in this group. Four patients died in the first year after the transplant due to intracranial bleeding, cerebral tumor recurrence, PTLD, and chronic rejection. There were two deaths at 3 years, one due to progressive renal failure secondary to cyclosporin toxicity and the other due to sepsis, portal hypertension, and recurrent bleeding. Vascular complications occurred in six (7.5%) patients and biliary complications in seven (8.7%).

CONCLUSIONS

These results, which represent the experience of a single institution over the last 6 years, indicate that ex situ split liver transplantation can be performed in children with good overall outcome and acceptable morbidity.

Predictors of survival after In vivo split liver transplantation: analysis of 110 consecutive patients

OBJECTIVE

To determine the factors that influence patient survival after in vivo split liver transplantation (SLT).

SUMMARY BACKGROUND DATA

Split liver transplantation is effective in expanding the donor pool, and its use reduces the number of deaths in patients awaiting orthotopic liver transplantation. Early SLTs were associated with poor outcomes, and acceptance of the technique has been slow. A better understanding of the factors that influence patient and graft survival would be useful in widening the application of SLT.

METHODS

During a 3.5-year period, 55 right and 55 left lateral in vivo split grafts were transplanted in 102 pediatric and adult recipients. The authors' in vivo split technique has been previously described. Median follow-up was 14.5 months. Recipient, donor, and surgical variables were analyzed for their effect on patient survival after SLT.

RESULTS

Overall survival rates of patients who received an SLT were not significantly different from those of patients who received whole organ transplants. Survival of left lateral segment recipients, at median follow-up time, was 76% versus 80% in patients receiving a trisegment. Fifty of 102 patients (49%) were high-risk urgent recipients (United Network for Organ Sharing [UNOS] status 1 and 2A) and 52 (51%) were nonurgent recipients (UNOS status 2B, 3). High-risk recipients had a survival rate significantly lower than that of nonurgent recipients. By univariate comparison, two variables-UNOS status and number of transplants per patient-were significantly associated with an increased risk of death. Preoperative recipient mechanical ventilation, preoperative prothrombin time, donor sodium level, donor length of hospital stay, and warm ischemia time approached significance. The type of graft (right vs. left) did not reduce the survival rate after transplantation. Multivariate logistic regression analysis identified UNOS status and length of donor hospital stay as independent predictors of survival.

CONCLUSIONS

Patient survival of in vivo SLT is not significantly different from that of whole-organ orthotopic liver transplantation. The variables affecting outcome of in vivo SLT are similar to those in whole-organ transplantation. in vivo SLT should be widely applied to expand a severely depleted donor pool.

Split liver transplantation

OBJECTIVE

This study reviews the indications, technical aspects, and experience with ex vivo and in situ split liver transplantation.

BACKGROUND

The shortage of cadaveric donor livers is the most significant factor inhibiting further application of liver transplantation for patients with end-stage liver disease. Pediatric recipients, although they represent only 15% to 20% of the liver transplant registrants, suffer the greatest from the scarcity of size-matched cadaveric organs. Split liver transplantation provides an ideal means to expand the donor pool for both children and adults.

METHODS

This review describes the evolution of split liver transplantation from reduced liver transplantation and living-related liver transplantation. The two types of split liver transplantation, ex vivo and in situ, are compared and contrasted, including the technique, selection of patients for each procedure, and the most current results.

RESULTS

Ex vivo splitting of the liver is performed on the bench after removal from the cadaver. It is usually divided into two grafts: segments 2 and 3 for children, and segments 4 to 8 for adults. Since 1990, 349 ex vivo grafts have been reported. Until recently, graft and patient survival rates have been lower and postoperative complication rates higher in ex vivo split grafts than in whole organ cadaveric transplantation. Further, the use of ex vivo split grafts has been relegated to the elective adult patient because of the high incidence of graft dysfunction (right graft) when placed in an emergent patient. Reasons for the poor function of ex vivo splits except in elective patients have focused on graft damage due to prolonged cold ischemia times and rewarming during the long benching procedure. In situ liver splitting is accomplished in a manner identical to the living donor procurement. This technique for liver splitting results in the same graft types as in the ex vivo technique. However, graft and patient survival rates reported for in situ split livers have exceeded 85% and 90%, respectively, with a lower incidence of postoperative complications, including biliary and reoperation for bleeding. These improved results have also been observed in the urgent patient.

CONCLUSION

Splitting of the cadaveric liver expands the donor pool of organs and may eliminate the need for living-related donation for children. Recent experience with the ex vivo technique, if applied to elective patients, results in patient and graft survival rates comparable to whole-organ transplantation, although postoperative complication rates are higher. In situ splitting provides two grafts of optimal quality that can be applied to the entire spectrum of transplant recipients: it is the method of choice for expanding the cadaver liver donor pool.

Split liver transplantation: King's College Hospital experience

BACKGROUND

The purpose of split liver transplantation is to increase the source of pediatric grafts without compromising the adult donor pool. Early results have been discouraging because of technical complications and selection of poor risk patients.

METHODS

The results of a single center experience of 41 split liver transplantations were analyzed. Patient and graft survival and complications related to the technique were analyzed.

RESULTS

Patient and graft survival for the whole group was 90% and 88% respectively at a median follow up of 12 months (range 6-70 months). Patient and graft survival for the right lobe graft was 95% and the left lateral segment 86% and 82% respectively. Four patients died, of which two of the patients were first two splits following technical complications. Two others died, one from cerebral lymphoma and the other of multiorgan failure secondary to sepsis. One patient has been retransplanted for chronic biliary sepsis.

CONCLUSION

Split liver transplantation has now become an acceptable treatment option for both adult and pediatric recipients with end stage liver disease. Right lobe recipients are not disadvantaged by the procedure. Good results can be achieved with better patient selection and by the use of good quality organs.

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.