Outcomes of Living Donor Transplantation: The Eastern Perspective

Historical Background

The first attempted and successful living donor liver transplants were undertaken in 1989 in the in Brazil and Australia. In the face of a scarcity of deceased donor liver grafts, living donor liver transplantation (LDLT) took a preeminent position in Asia. In the early series the recipients were children and the parents donated their left livers for the transplant. Brain death was legislated in many Asian countries, including Taiwan (1987), Japan (1997), and Korea (2000). Clear guidelines for organ procurement from brain dead donors have also been set by the government of Hong Kong (1995) based on the criteria endorsed by the Medical Royal Colleges of the United Kingdom. However, as a result of various cultural and social reasons, the supply of deceased donor organs for transplantation has remained low in Asia. There have been practically no deceased donor organs for transplantation in Japan because of the poor acceptance of the brain-death concept by the public.

Following the success in pediatric LDLT, Shinshu University performed the first adult LDLT and a left liver graft was used. Kyoto University improvised right liver LDLT for a 9-year-old girl to avoid the technical difficulties of using a left liver graft with extremely tapered segment II and III hepatic arteries. In 1996 at Queen Mary Hospital, the University of Hong Kong, to meet the metabolic demand of a recipient (90 kg) with acute deterioration from Wilson’s disease, procured the right liver (including the middle hepatic vein [MHV]) from the elder brother donor (74 kg) for LDLT. Chen of Taiwan performed the first deceased donor liver transplantation (DDLT) in Asia. His center in Kaohsiung is a high-volume center with outstanding outcomes. The Asan Medical Center in Korea has the highest number of LDLTs in the world and with excellent results.

Donor Outcomes

Donor safety is fundamental to LDLT. For a recipient with a larger body size than the donor, the right liver graft is often required. The unsatisfactory outcome of left-liver LDLT persuaded centers to use the right liver when necessary. When LDLT evolved from transplanting only children to transplanting adults and from using the left liver to using the right liver, the concerns for donor safety escalated. The more rapid recovery of liver function of the left liver donor is obvious. Based on over 12,000 living donor hepatectomies, the estimated donor mortality rate of donors for the right and left livers is 0.5% and 0.1%, respectively.

When the right liver graft was first used, there was much reluctance to including the MHV in the graft. Nevertheless, venous congestion of the right anterior section leading to graft dysfunction and even mortality was observed when the MHV was not included in the graft. Kyoto University included the MHV while preserving intact the segment IVb hepatic vein draining the cephalic portion of segment IV. The center also used an interpositional vein graft to lengthen the MHV for anastomosis to the inferior vena cava. Ingenious techniques of using venous grafts and cadaveric inferior vena cava were designed for reconstructing the segment V and VIII hepatic vein branches. Chen of Taiwan selectively includes the MHV if the right liver graft is less than 50% of the recipient standard liver volume. Kyoto University includes the MHV when the right liver graft is MHV dominant or the graft-to-recipient weight ratio is below 1%. The donor remnant left liver should be over 35% of the total liver volume unless the donor is young and the quality of the liver is good.

In 1996 the Hong Kong group included the MHV in the right liver graft and preserved the segment IVb hepatic vein irrespective of the anatomical variation of segment IV hepatic vein. It has been shown that donors of the right liver had comparable surgical outcomes irrespective of sacrifice of the MHV or otherwise. The MHV and the right hepatic vein are merged to form a single cuff for easy implantation in the inferior vena cava. The simplicity of technique and minimal blood loss ensure reproducibility of results and transferability of skills.

Reporting of living liver donor morbidity and mortality is not mandatory. Nevertheless, a multicenter survey was conducted for five Asian liver transplant centers, and the outcomes of a total of 1,508 living liver donors were reported a decade ago. The complication rate was higher in right liver (28%) than left lateral section (9.3%) or left liver (7.5%) donors. There was then no donor mortality. More recently the Japanese Liver Transplantation Society surveyed the outcomes of living liver donors of 38 centers until the period ending December 2006. In a survey of 38 Japanese centers, of 3565 donors, one donor died (0.03%) and 299 donors (8.4%) developed complications.

A recent global review by Ringe and Strong reported 33 living liver donor deaths. Well-documented donor deaths in Asia were from Hong Kong, Kyoto, and Singapore. A 54-year-old female donor in Hong Kong died from a chronic duodenal ulcer perforating into the inferior vena cava 10 weeks after donation. A female donor in Kyoto donated her right liver, including the MHV, to her adolescent daughter. Her liver had undiagnosed nonalcoholic steatohepatitis, and the remnant left liver was 28% of her total liver volume. A 39-year-old male donor in Singapore died from acute myocardial infarction on the second postoperative day despite good cardiac function and passing the treadmill test preoperatively. Two donor deaths in India were reported by the Indian medical journals and newspapers.

The moment that anesthesia starts and a skin incision is made on the potential donor turns the normal subject into a patient. Deranged physiological function emerges until the remnant liver regenerates sufficiently to restore the well-being of the donor. The liver function will become normal within weeks, but there is a demonstrable elevation of serum liver enzyme levels, decrease in white cell and platelet counts, and increase in spleen size when the quality of life, in particular the physical domains, deteriorates substantially during the early postoperative period. Recovery to near-normal levels is expected for the majority of living liver donors. It is most important to identify potential donors who are more prone to having poor long-term physical and psychological outcomes after donation. Older donors fall into this group.