Technique May Enhance Donor Organ Preservation
Almost 75 percent of liver transplant recipients survive at least five years after surgery.* But the problem for many patients with liver disease is surviving long enough to receive a transplant; after more than 6,000 liver transplants are performed each year, about 10,000 patients still remain on the waiting list.**
Washington University transplant surgeons at Barnes-Jewish Hospital have addressed the organ shortage in the past through public donor initiatives and by finding ways to make marginal organs suitable for transplant. Now they are investigating a technique that may improve the donor organ preservation procedure, so that fewer organs are lost to tissue damage experienced during this crucial part of the complex transplant process.
Donated livers are currently flushed with a cold preservation solution and iced down with sterile slush at the time the organ is recovered. The process contributes to ischemia/reperfusion injury — inflammatory damage that occurs when blood flow is temporarily interrupted and then restored during transplant.
“If the organ is marginal — with more than 30 percent affected by fatty liver disease — the injury will be worse and can make it unsuitable for transplant,” says William Chapman, MD, the Eugene M. Bricker Professor and division chief.
Washington University will be one of about 10 to 15 U.S. centers testing normothermic extracorporeal liver perfusion (NELP), which involves circulating oxygenated warm blood, nutrients and medications to the donor organ to keep it metabolically active until transplant. The method has shown promise in Europe and Canada; in animal studies, Chapman has found that NELP reduces ischemia/reperfusion injury, protects from cold injury and allows the transplant team more time to assess organ viability before transplantation by evaluating clotting function, clearance of acid, bile production and various pressures.
“Based on our lab results and what the trials show, this method could be an important way for us to address the donor organ shortage,” says Chapman.
*U.S. Department of Health and Human Services **American Liver Foundation
Washington University transplant surgeons at Barnes-Jewish Hospital are leaders in the movement toward using dedicated facilities based at organ-procurement organizations (OPOs) to recover donor organs, rather than recovering organs in the hospital setting. They have published groundbreaking research on the benefits of OPO facilities and also use such a facility at Mid-America Transplant Services (MTS) to recover about 90 percent of their program’s donated organs — the highest rate of any transplant group in the country. In recent research, M.B. Majella Doyle, MD, MBA, and Division Chief William Chapman, MD, found that OPO facilities reduce donor-organ recovery costs by 54 percent and increase organ yield compared with hospital-based recovery.
Thalachallour Mohanakumar, PHD, who engaged in groundbreaking transplant research for 28 years at Washington University, will be the first speaker in a professorship honoring him in spring 2017. Mohanakumar made seminal contributions on the structure and function of peptides and their role in preventing organ rejection in kidney and lung transplants, and in defining human immune responses to pig organs. He is recognized as one of the nation’s top NIH-funded scientists.
St. Louis Children’s Hospital hosted the National Studies in Pediatric Liver Transplantation (SPLIT) Conference, a CME event, in September 2016. SPLIT is a multidisciplinary community of pediatric health professionals across the United States and Canada working to advance knowledge in pediatric liver transplantation.