Evolving surgical approaches in liver transplantation.

The Dumount-UCLA Transplant Center, Ronald-Reagan UCLA Medical Center, Los Angeles, California.

The growing discrepancy between the need and the availability of donor livers has resulted in evolving surgical approaches in liver transplantation during the last two decades to expand the donor pool. One approach is to transplant partial grafts, obtained either from a living donor or splitting a cadaveric donor liver. For both surgical methods, it is important to obtain a minimal viable graft volume to prevent small-for-size syndrome and graft failure. This minimal volume, expressed as graft-to-whole body ratio, must be between 0.8 and 1%. Living donor liver transplantation (LDLT) became the primary transplant option in many Asian countries and is increasingly performed as an adjunct transplant option in countries with low donation rates. Split liver transplantation (SLT) is a surgical method that creates two allografts from one deceased donor. The most widely used splitting technique is the division of the liver into a left lateral sectoral graft (segments 2 and 3) for a pediatric patient and a right trisegmental graft (segments 1 and 4 to 8) for an adult patient. Both LDLT and SLT are also important and established methods for the treatment of pediatric patients. Another evolving surgical approach is auxiliary liver transplantation, which describes the transplanting a whole or partial graft with preservation of the partial native liver. This bridging technique is applied in patients with fulminate liver failure and should allow the regeneration of the injured liver with the potential to discontinue immunosuppression. Other methods such as xenotransplantation, as well as hepatocyte and stem cell transplantation, are promising approaches that are still in experimental phases.