Why Living Liver Donation?
There is a tremendous need for liver transplants that isn’t being met through deceased donation. UNOS figures show nearly 14,0000 people await liver transplants, yet only about 7,000 transplants actually occur each year. There is an enormous gap.
Enter living donation. The special characteristics of the human liver make living donation unique. While each of us has only one liver, it is a large, segmented organ that regenerates, allowing a surgeon to remove a portion yet have both the recipient and donor with larger livers within a matter of a few months.
Living donation has important advantages over deceased donation:
- The waiting time for a transplant recipient can be significantly reduced.
- The procedure can be scheduled at a time convenient for both the donor and recipient.
- The time between procurement of the organ and transplantation to the recipient is minimized.
One additional advantage of living donation that applies to kidney donation that does not appear to apply to liver donation is that the quality of the donated organ is better and has a higher chance of survival. That is, experience has not shown a clear and sizable advantage of living liver donation over deceased donation in terms of graft (donated organ) survival (in contrast to the clear advantage of living kidney donation over deceased donation). Graft survival results for deceased and living liver donors (2008 – 2015) are shown in the table below:
Liver Graft Survival Rates
Time after donation
From deceased donors
From living donors
The sample size of living liver donors is fairly small, and the characteristics can be a consequence of factors other than demographics. With that caution, here is a summary of living donor features:
- Most (64.1%) were between the ages of 18 and 34.
- Two-thirds were white, 20.5% black, and 12.8% Hispanic.
- Half were male, and half were female.
- 58.6% were blood type O, 32.9% were type A, 8.6% type B, and none were type AB.
- The majority of donors (84.2%) were parents of the recipient, 7.9% children, 2.6% identical twins, no siblings, 5.3% other relatives, and no unrelated donors. (Note that UNOS did not have data on the relationship for nearly half the donors.)
These results, combined with evidence that the majority of liver transplant recipients are children under age 18, suggest living liver transplants are mostly from parent to child.
Living liver donation grew out of experience with deceased donations, specifically the use of “reduced” or “split-liver” donations using just a portion of the liver. Physicians learned that only a portion of a donated liver was needed. The first living transplant was from an adult to a child performed in Australia in 1989. The procedure is now common at major pediatric centers.
More recently, techniques have been developed for adult-to-adult donation, which requires a larger portion of the donor liver. The first such donation occurred in 1995.
As with kidney donation, there has been an increase in “nondirected” or living unrelated donation from strangers. The first such donation in the US occurred in 1999. There have also been a small but increasing number of paired donations, the first of which was performed in 2014.