Bringing Lungs to Bloom
Fifty years ago, U-M surgeon Robert Bartlett helped invent a life-saving procedure called Extracorporeal Membrane Oxygenation (ECMO). Now researchers are using the next-generation of ECMO to give lungs a new life.
In the sub-basement of a building on the U-M’s medical campus, 20 people in blue scrubs and white coats crowd into a surgical suite in the U-M’s Extracorporeal Life Support Research Laboratory. They are learning how to evaluate lungs for potential transplantation outside the body during a process called ex vivo lung perfusion.
These surgeons and technicians are preparing for a groundbreaking clinical trial at the U-M Health System. Today they are training with animal lungs, but once the study begins, they will be working with human lungs. Called the Novel Lung Trial, it could mean the difference between life and death to thousands of people who need a lung transplant.
The trial is sponsored by XVIVO Perfusion, the Swedish-based manufacturer of a machine called an XVIVO Perfusion System (XPS) and the perfusion solution called STEEN Solution, both used in the study. After surgeons remove lungs and attach them to the machine, the XPS flushes them with STEEN Solution and warms them to normal body temperature, inflates the lungs to their normal size and then tests them to determine if the lungs are healthy enough to transplant. The environment inside the system can allow some damaged lungs to heal themselves, or recondition. The machine’s function, though, is to allow physicians to evaluate a lung for transplant.
Ex vivo lung perfusion is a direct descendant of a life-saving procedure called extracorporeal membrane oxygenation (ECMO), which was developed by U-M surgeon Robert Bartlett (M.D. 1963) and his colleagues during the 1960s and 1970s to treat children dying from acute respiratory failure. The device, invented by a small group of young surgeons to heal sick lungs inside the body, has evolved into a machine that can give damaged lungs a chance to heal outside the body.
It’s the latest in a long line of research advances taking place in the U-M’s Extracorporeal Life Support (ECLS) Research Laboratory. Bartlett, now a professor emeritus of surgery, brought the lab to U-M in 1980 when he joined the Medical School’s faculty. Part of the Department of Surgery, the lab has an international reputation for pushing the boundaries of knowledge about artificial organs and organ transplants.
“This laboratory has always been focused on the big clinical problems and what we can do to solve them quickly,” says Bartlett, who has an enviable record of 40 consecutive years of NIH research funding. “We can’t always do it within five years, but that is always our goal.”
Advances in ECLS technology are bringing us closer to what Bartlett says is the field’s ultimate goal. It’s called organ banking or organ conditioning. The objective is to keep human organs viable and healthy outside the body for several days — much longer than the current limit of a few hours. Once researchers figure out how to do this, Bartlett says ECLS will revolutionize the practice of medicine.
“Not only could we have many more organs available for transplantation, we could have organs that do things — livers that make albumin and clotting factors, bone marrow that makes red blood cells,” says Bartlett. “We could take out a liver that’s full of cancer, treat it and then return it to the patient. We think all those things could be possible.”
Advanced ECLS technology is already being used clinically in Canada and Europe either as a temporary bridge to lung transplant, or to evaluate health of lungs awaiting transplant. Researchers are developing technology to support other organs like hearts, livers and kidneys outside the body, but this work is still in the animal research stage.
Bartlett is not the only U-M physician who is enthusiastic about what ECLS research could mean to thousands of patients on the waiting list for a donor organ and to the doctors who care for them.
“I think that the number of lungs available for transplant will be 50 percent greater five to 10 years from now, because of this technology,” says Jeffrey Punch (M.D. 1986, Residency 1992, Fellowship 1994), a U-M professor of surgery and head of the Section of Transplantation at UMHS. “I hope we’ll see renewed interest in doing this for livers and kidneys, as well.”