Some of the most significant advances in Liver transplant were brought about by the need to find a solution for the lack of available organs for pediatric liver transplants. The epidemiology of irreversible liver failure and that of brain death widely differ from each other in pediatric patients (Box01.ppt). Most children eligible for liver transplants are under two years of age, whereas few children who die of problems that cause brain death are under the age of five. For these reasons, before the advent of new surgical techniques, the mortality rate of children on the waiting list for pediatric transplants was around 50%.

Pediatric Liver transplant was dramatically changed by new surgical techniques developed to help reduce the liver's size to make it compatible with the recipient's size. From the liver of a cadaveric donor weighing up to 12 times more than the recipient, a liver portion (usually including the left lateral liver segments) can be procured and implanted in a child weighing less than 10 kilos (Ridotto.avi). However, the shortcoming of this technique is that organs usually allocated for adult transplants are used for pediatric transplants.
To avoid this problem, at the end of the 1980s two new transplant techniques were implemented: the split liver and the living donor transplant. These methods developed and progressed in parallel: the upgrade of living donor techniques allowed for improvement in the split liver method, making it safe and effective for transplanting both pediatric and adult patients. In many countries, the excellent results of "split” transplants essentially have eliminated the need for a living donor transplant for pediatric recipients. The pediatric population has thus turned into a privileged subgroup of patients eligible for a liver transplant, with approximately a zero mortality rate on the waiting list.

The split liver technique provides two organs, which can usually be implanted in an adult recipient and in a child, from a single cadaveric donor (Split convenzionale(2).avi). Although the first results (Box02.ppt) of this technique were not comparable with what was achieved by conventional transplant techniques, later technical developments brought about so many improvements (Box03.ppt) that the split liver has become the first-choice for pediatric transplants.
The transplant of a liver portion procured from either a cadaveric or a living donor was at first developed to overcome the shortage of organs for pediatric transplants, but has more recently become a way to fill in the widening gap between number of cadaveric donors, which in many countries has apparently reached a plateau, and ever-increasing number of adult patients who are candidates for a liver transplant.

In this context, living donor transplantation is increasingly utilized in its technical variant of procurement and transplant of the right hepatic lobe. Unlike the pediatric recipient, where it must be ensured the transplanted liver portion is not too large, it is essential that the adult recipient receive a liver mass of adequate volume. As a general rule, the transplanted liver portion should at least be 1% of the recipient's body weight. In most cases, the volume of the right hepatic lobe meets this requirement, meaning that an adult liver is able to keep two adults alive: the donor and the recipient.

A surgery comparable to the procedure on the living donor can be performed on the cadaveric donor to obtain two grafts of adequate size to be transplanted into two adult recipients, shifting rightwards – as compared to the conventional split liver technique – the plane along which the liver parenchyma is divided (Da split a splittone.avi). Hence the split liver technique for two adult recipients may in the future contribute towards a significant increase in the number of liver transplants (Split per adulti.avi).