Artificial liver trials show progress,
as transplant
candidates wait
By Mary Beth Reilly / Medical School Communications
Four years after the first American clinical trial of an experimental
artificial liver system began at the U-M Health System (UMHS), its
leader says he is encouraged by the results thus far. Dr. Robert
Bartlett says he is optimistic about the system's potential to help
more liver-failure patients stay alive until they receive a liver
transplant or recover without one.
Already, 20 desperately ill patients have used the device in a
phase I trial, Bartlett says. Of the six patients who went on to
receive a transplant, three are still alive but continue to have
liver damage. Two others recovered liver function without needing
a transplant.
The system, called albumin dialysis, uses special filters and proteins
to remove toxic substances from the blood while sparing helpful
compounds.
Results from Germany, where the system was invented, and from the
three other American hospitals now testing it, also give Bartlett
hope. The system appears safe, able to reduce blood toxins, and
able to reverse coma and shock.
Liver transplants offer hope for many people, but there aren't
enough organs from deceased and living donors to go around. In 2001,
5,177 Americans received new livers, but another 1,975 died waiting.
Nearly 1,000 of the more than 17,460 patients now waiting are children
and teenagers.
A new liver transplant candidate system instituted by the United
Network for Organ Sharing in 2001 places the sickest patients called
status 1 at the top of the list to receive livers as they become
available. But that means patients are most likely to receive a
liver when they have the least amount of time to wait. Status 1
patients are defined as having fewer than seven days to live. That
makes artificial liver support more crucial than ever, Bartlett
says.
"Current and future clinical trials will help further establish
how well albumin dialysis might help buy time for the 17,400 Americans
now waiting for a liver transplant, and the tens of thousands more
on waiting lists worldwide," says Bartlett, who is a professor of
surgery, director of critical care and head of the extracorporeal
life support team at UMHS.
"We must also explore whether the system can help patients regain
function in their own livers, as two of our patients did," he says.
"Currently, we are using albumin dialysis only for patients in the
intensive-care unit who need emergency liver transplants, but we
will soon extend the treatment to other patients with liver disease."
U-M is preparing to participate in a multi-center, randomized and
controlled trial comparing albumin dialysis with standard medical
treatment in chronic liver failure patients who are in hepatic comas a
neurological state caused by liver failure. The new U-M trial, led
by U-M gastroenterologist Dr. Robert Fontana, will begin in early
2003.
In addition to Bartlett, other U-M researchers are Dr. Fresca Swaniker,
Dr. John Magee, Dr. Jeffrey Punch and Dr. Steve Rudich.
