January 30, 2012
Live liver donation safer than previously thought
Surgery to donate portion of liver does not interfere with long, healthy life
People who donate a portion of their livers for transplant to a relative or friend whose liver is failing can generally expect to recover safely from the donation surgery and live a long, healthy life, Johns Hopkins researchers have found.
“The donor process is safer than some have previously thought,” said transplant surgeon Dorry L. Segev, an associate professor of surgery and epidemiology at the Johns Hopkins University School of Medicine and leader of the study published in the February issue of the journal Gastroenterology. “Live liver donation is a serious operation with serious risks. However, in this largest study ever conducted in the United States, we have shown that it is safer than many previously believed, with a risk of death of 1.7 per thousand donors.”
The only treatment for end stage liver disease is transplant. Without a functioning liver, patients in liver failure die. Safe live liver donation is possible because the liver is an organ that regenerates itself relatively quickly, Segev notes, allowing the harvest of a small portion of the organ that, when transplanted, grows into a liver large enough to perform its crucial roles in blood detoxification, digestion and metabolism. The regenerative ability also means that donors can survive well until theirs, too, regrow.
A decade ago, surgeons across the United States performed an estimated 500 live liver transplants a year. In 2002, however, the death of a live liver donor was highly publicized, and since then, live liver donation may have been perceived as more dangerous than it actually is, Segev says. Now, he says, only 200 to 300 of these surgeries are performed annually, compared to 6,000 live kidney donations.
More than 16,000 people are currently on the waiting list for a liver transplant in the United States, while only around 6,000 livers from deceased donors are available. “For many [patients], the risk of dying on the waiting list is higher than the chance of getting a deceased donor transplant,” Segev said. “For the right patients, with the right needs and the right donors, live donor transplantation can be the best treatment option, and this study reassures us that the risk of a catastrophic complication remains low.”
To determine the safety of live liver donation, Segev and his colleagues combed data from all 4,111 donors in the United States between April 1994 and March 2011, and followed patients for an average of 7.6 years. Over that period, there were seven donor deaths in the 90 days following surgery, but the researchers say that the long-term survival rate for donors was equal overall to the long-term survival of live kidney donors and a healthy control group culled from the National Health and Nutrition Survey.
Although the rate of live liver donor death was relatively low, Segev says that it is still five times that of the risk of death for live kidney donors. A study by Segev published in the Journal of the American Medical Association in March 2010 found that the rate of death in live kidney donation in the United States is 3.1 in 10,000. However, kidney donation is a simpler process, Segev notes. The operation itself is less complicated, and kidney donors are left with one completely intact healthy kidney, which is typically able to compensate for the function of the one removed. By contrast, if a donor does not have enough healthy liver remaining after donation, he or she may not have enough liver function to get through the regeneration process, and might actually need a transplant to survive.
Segev says that he was particularly interested in studying the outcomes for donors because most of those who offer to give up part of an organ come to the process very healthy. “The ideal risk of death from donating an organ is zero, and we work as hard as we can to seek that ideal,” said Segev, director of clinical research in Transplant Surgery at Johns Hopkins. “But in these serious, major operations, it is unlikely the risk will ever be zero.”
Other Johns Hopkins researchers involved in the study are Abimereki D. Muzaale, Nabil N. Dagher and Robert A. Montgomery.