She only needed a little bit. Tiny 5-month-old Kara French was suffering from liver dysfunction and was scheduled to receive a liver transplant, but she didn't require an entire liver. Since the liver can regenerate itself over time, it was decided that French, who was living in Miami, would get a small part of the donated liver and the remainder — about 75 percent — would go to Victor Billingsley, a father of three living in Mississippi. With the donor in Baton Rouge, the two surgical teams — one from Holtz Children's Hospital in Miami, and the other from Tulane University and Clinic in New Orleans — would have to act fast. Dr. Sandy Florman, director of Tulane's Abdominal Transplant Institute , who completed the Billingsley's transplant talks about the speed of the process, from identifying a donor to the organ functioning in the recipient, and how the liver can amazingly be split to save two lives instead of one.
Q: Procuring an organ for transplantation is something that has to take place quickly. Describe the procedure in this particular case.
A: With the split liver transplant, we shared the liver with Miami. They had to get a plane, fly in, and we sent our team to split it with them in Baton Rouge. I think the time from when we got the call and were in Baton Rouge was probably eight to 12 hours. Then they have to drive back, which is an hour and a half. We try to time things so that while they're on their way back, we're getting Billingsley asleep — it takes a little time to get his liver out too. The cold ischemia time — the time from when we take the organ out of the donor until all the blood vessels are reconnected in the recipient and blood is flowing back through it — is very important. We can't keep organs out indefinitely because they don't work if you do that. We like to get [the liver] in within 10 hours. His was back in him within four hours of it being taken out in Baton Rouge. That's very fast.
Q: Is splitting a liver becoming common?
A: If it became more common, that would be great. It's estimated that there are 1,000 livers a year in the United States that would be eligible to be split. We have certain criteria such as it having to be a young donor, and the donor can't be on a lot of medicine. If we identify all the appropriate candidates, we could split up to 1,000 livers. Unfortunately for us, for a lot of reasons, that doesn't happen and only about 100-150 of these are done a year. There's a big push by UNOS (United Network for Organ Sharing) ... to help different centers identify appropriate candidates, because we might not have had a baby to put the little part in or vice versa. So a relationship like we have with Miami works well, and we're going to try build our relationship with them and share our lists with them because it worked out so well.
Q: When an organ is split, how do you determine how much each patient receives?
A: There are only certain ways to split a liver that maintain the anatomy so that it can be put into the recipient. Basically, we can take a small piece for a baby, which is 25 percent of an adult's liver. In rare cases, we can split the liver right down the middle and it's a 60/40 split. We try to transplant the bigger piece in the bigger adult. The science is critical and that's why a lot of places don't do it. The stakes become much higher when you cut the liver in half and are sewing blood vessels that are a half or a third the size of the main blood vessels. It's all done with microscopes.
Q: What's the success rate?
A: In the right hands, it's quite high. It's not for every center; you have to have experience with this, which is limited also. I went to New York and learned a lot of these techniques.
Q: A patient can receive only a portion of a liver and the liver will then regenerate itself until it is full size. How much is necessary for this to happen?
A: The early Greeks recognized this. You heard about Prometheus, who stole fire from Zeus? He was punished by being chained to a rock and every day a bird ate out his liver and at night while the bird slept, the liver re-grew. It doesn't happen quite that quickly, but it is amazing. You need a certain amount of liver. I can't give you one perfect answer because it depends on a lot of factors ... but we're all born with much more liver than we need. In fact, if you have a normal, healthy liver, you probably only need about 25 percent of what you have to sustain life. Then that liver could regrow back to the 100 percent volume you originally had. Interestingly, from the second you start cutting liver, it starts to regenerate. Within four weeks, 90 percent of the liver is regenerated. The last 10 percent takes six months or so.
Q: What if you transplant too much liver?
A: It can also shrink down. If we put a piece of liver that's a little bit more than that baby needs, as long as it's not too big and you can close the belly, the liver within four weeks will shrink down to the size that the baby needs.
Q: Both of the patients were on a liver transplant list less than two months. Are short waiting times becoming more common?
A: You can't just give a partial liver to anybody. The sicker you are, the more you require the whole liver, so this is one of those times when we look at the list and look for someone who is appropriate to take it. The UNOS rules are that the person who is the sickest with the highest score waiting gets the liver. The liver was given to the baby, but it was too big, so the Miami people said, "We're going to split it." UNOS called us and asked if we wanted the other side. We agreed to that.