MUSC uses organ perfusion machine to increase access to liver transplants

physicians have onsite training with the new device — Tracy Rice, M.D., (center) during MUSC’s onsite training and simulation day with John McGillicuddy, M.D. (right), and Santosh Nagaraju, M.D. (left).

The OrganOx metra® normothermic machine supplies the donor organ with warmed, oxygenated blood, improving organ viability and giving transplant surgeons more logistical flexibility

by Celia Spell

This past October, MUSC Health used a normothermic perfusion machine during a liver transplant procedure for the first time in an effort to provide more livers to those who need them.

Since then, the hospital has performed 5 liver transplants using the device.

As is the case with most organ transplants, there are more people on the waiting list for a liver than there are livers available. On the MUSC waitlist alone, there are 110 people in SC waiting for a liver. Nationally, there are over 10,000 people waiting. But with technology that can pump warm, oxygenated blood through the donated liver, surgeons can preserve and test the viability of donated organs in a way they never could before.

Tracy Rice, M.D., a surgeon at MUSC, first started working with the normothermic perfusion machine from OrganOx in 2019 as part of the device’s clinical trials for FDA approval at Washington University School of Medicine in St. Louis. The first procedure using the warm perfusion method was performed in 2000 in Lund, Sweden, but it did not receive FDA approval in the United States until 2021.

The team posed for a photo after MUSC's first surgery with the OrganOx metra normothermic machine in October.

MUSC is the first hospital in the state to use this machine, and it’s the 20th center overall in the country to adopt this technology.

“As transplant surgeons,” Rice said, “we’re always looking for ways to help the transplant community and expand patients’ access to the organs they need. There is a severe shortage of viable livers that meet the needs of patients on the waiting list.”

According to Rice, without these life-saving transplants, more than 10 people die in the U.S. every day waiting for a liver transplant. “This pump can help with that,” she said.

Traditionally an organ is stored cold after it is removed from the donor and before it is transplanted into the recipient. With this static cold storage method, the organ is flushed and stored using a cold preservation solution. To ensure maximum viability, surgeons then only have 6-8 hours to transport and transplant the liver to the patient when using static cold storage, and keeping the organ cold can result in cell death and stress or shock once transplanted.

Warm perfusion using the OrganOx metra® machine is different. With it, the liver never stops functioning. The donor liver is continuously perfused with oxygenated blood, medications and nutrients at a normal body temperature with near-physiological pressures and flows – preserving the liver for up to 12 hours. On the machine, the organ functions similarly to how it would inside the human body. The liver even produces bile like it normally would.

This extra time offers multiple advantages to the liver transplant team, according to Rice. By expanding the time window, surgeons can wait until a full multidisciplinary transplant team can be assembled to provide the safest surgical setting possible. They can also transport the liver from farther away to a patient in need. Finally, it allows physicians to properly assess the health of the liver before transplanting it into a patient, which is particularly critical when evaluating livers donated from older or obese patients with higher risk factors.

Liver function, Rice explains, can’t be assessed when using static cold storage, so physicians often discard livers from donors with known risk factors not knowing if they may indeed be healthy. One such risk factor are organs donated after circulatory death, or DCD, where a donor has a cardiac-related death. A DCD liver carries a higher risk of complication, but that risk can be managed effectively using the warm perfusion method. MUSC Health also performed the first DCD heart transplant in the state last fall using a similar ex vivo perfusion machine.

“We’ve come to learn that your liver will often outlive you,” she said. “And that’s our goal: to transplant livers that will last the rest of the new recipient’s life.” A liver from an older or obese patient can still be perfectly healthy, so Rice emphasizes the importance of testing and assessing all organs in an effort to decrease the rate of discarded organs.

“Overall, using machines like the OrganOx metra® increases access to transplant,” Rice said. “Transplant is such a limited and critical resource, and it gives more South Carolinians the opportunity for this life-saving option. We have more data and the ability to transplant more people safely.”