Split Vs. Whole Liver Transplantation
Caveat: The OPTN/UNOS Ethics Committee acknowledges that splitting cadaveric livers for transplantation is an evolving technology. Until this transplantation modality is recognized as accepted practice, the Committee reserves the right to revisit/revise their thoughts and opinions regarding this procedure. This paper is not to be construed as a recommendation or expectation for the formation of a national policy requiring split liver transplantation.
Technological advances in hepatic surgery have facilitated the splitting of cadaveric livers, thereby increasing the supply of donor organs. However, the advances in this particular technology have outpaced the psychological and sociologic repercussions, and have resulted in difficult ethical issues. Specifically, dilemmas associated with ownership and stewardship of a limited resource become apparent. For example, if a patient has ascended to the top of the waiting list, should they be entitled to receive a whole liver even if the organ could be split to benefit two patients?
Based on previous experience, it is apparent that if a potential recipient is informed of an increased risk of morbidity (i.e., biliary complications) associated with receiving a split liver, they may decline permission to split the liver. Since the person at the top of the list may be perceived to be entitled to receive the liver, it could be considered as coercion if they were told the liver would be offered to the next recipient who would be willing to receive a split liver. Unfortunately, this scenario could result in the wasting a scarce national resource, which could be viewed as poor stewardship of this valuable resource. The Ethics Committee provides the following discussion and suggestions in an effort to optimize utilization of livers with the potential for split liver transplantation.
One of the paramount responsibilities of transplant surgeons is to inform potential recipients as to the current practices of their transplant program regarding split liver transplantation, the risks involved, the potential for increased morbidity requiring additional interventional/surgical procedures and hospital stay, and the program's outcome data regarding these procedures. Furthermore, these surgeon/patient
The morbidity associated with split livers will be program-specific and associated with a learning curve. Several centers are presently reporting excellent results with split livers resulting in two grafts: 1) a right trisegmental graft which includes segments I, IV, V, VI, VII, and VIII (trisegment split); and 2) a left graft consisting of the left lateral lobe including segments II and III (LLL split). The left lateral lobe is utilized most commonly for transplantation into a pediatric recipient, with the right trisegmental graft being transplanted into an adult recipient. This is the type of split procedure employed by programs reporting excellent results with split livers. In these reports, the morbidity associated with the split liver transplants is similar to that for recipients of whole organ transplants. Programs performing the split liver procedure utilize only "optimal donors," increasing the probability of a good outcome.
It should be recognized that there has not been as much reported experience with "true" split livers. A true split produces a right and left lobe with enough mass to be transplanted into two adults. In the initial experience of a true split procedure, outcomes demonstrate increased morbidity and longer hospitalizations requiring additional surgery as compared to whole organ liver transplants. With increasing numbers of living donor liver transplants being performed into adult recipients, the scope of knowledge surrounding the development of true split livers will undoubtedly improve. An anticipated benefit of true split liver transplant will hopefully be morbidity rates approximating the same rates seen with right trisegmental/left lateral lobe split grafts. Until such time, however, potential recipients should be informed of the increased risks of receiving a right or left lobe from a true split liver. Once more, the discussion as to the acceptance of a true split liver transplant will need to occur well in advance of the time of transplant, a time when potential recipients are not under undo pressure.
With all of the aforementioned facts and information disclosed, it is necessary to acknowledge that not all liver transplant programs are capable of splitting livers at this time, nor are all of the programs equally successful in performing split liver procedures. However, some liver transplant programs employing the trisegment/LLL split procedure report morbidity and outcomes that are similar to those of whole liver transplants. When the morbidity and outcomes of these two surgical procedures are similar, the trisegment/LLL split liver transplant is comparable with the previously accepted standard of care, thus becoming an acceptable standard of care. Consequently, in transplant centers where these split liver and whole liver outcomes are similar, patients at the top of the liver list should not be given the liberty of
All things considered, it remains the right of a patient to refuse a liver segment that has been allocated to him or her. Additionally, a patient should not be penalized for refusing a split liver. Refusal of any organ is an unequivocal right of the patient. However, this does not give the patient any entitlement to a
The willingness of an adult patient to accept a remaining portion of a split liver from a pediatric transplant procedure should be documented. Under these circumstances, the adult recipient at the top of the UNOS/regional list who has previously consented to accepting a split would be offered the remaining right lobe graft. By having the discussion of risks involved with split liver transplantation prior to the time of transplant, rapid placement of the remaining lobe can occur. Listed patients who have previously indicated an unwillingness to accept part of a split liver should nevertheless be re-offered the potential option of accepting a split liver one or more times during the waiting period; patients may change their minds as circumstances change.
As the technology surrounding hepatic transplantation continues to advance, it is essential to develop ethically acceptable guidelines for these surgical options. The Ethics Committee affirms the following considerations to ensure responsible and ethical liver transplantation: