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Clinical Innovations, Policy Drive Improved Organ Preservation and Increased Transplants
Matthew Fox, MSHC
May 6, 2026
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A living donor kidney transplant is performed by Dr. Turgeon (second from left) at the Dell Seton Medical Center at The University of Texas at Austin.
Organ transplantation in the US experienced a strong year in 2025, with a record 49,064 transplants performed.
This figure is only the latest representation of a growing, positive trend, where organ transplant totals have increased each year for more than a decade (excluding 2020 due to COVID-19 restrictions).1
These increases reflect continued advances across transplant care, where surgeons are often taking the lead in improving access to and use of organs from an increasingly diverse group of donors, both living and deceased.
Even limiting the focus on the two most-needed and most-transplanted organs, kidneys and livers, reveals the many ways the system is advancing, often based on transplant surgeons’ expertise and experience as the functional crux of organ transplantation.
This article examines recent clinical advances, research, and policy developments that are driving the ongoing success of the US transplant system—as well as the work that remains to be done.
Ischemia-Reperfusion Injuries Remain a Challenge
Because donor organs are such a valuable and scarce resource, approaches to managing organ shortages and broadening the pool of usable organs involve both scientific and clinical advancements, as well as policy changes.
A primary clinical focus in solid organ transplantation is maintaining organ function during procurement, transport, and implantation. During the critical period when the organ is outside the body, it is at risk of ischemia, and then possibly a reperfusion injury once it is placed.
“Any organ, even the organ from a living donor, undergoes a period of ischemia once it is removed, with the damage to an organ determined by organ-specific aspects, length of ischemia, and the modality of organ preservation,” said Stefan G. Tullius, MD, PhD, FACS, a kidney and pancreas transplant surgeon, program director of the Division of Transplant Surgery, and the Joseph E. Murray, MD, Endowed Chair in Transplant Surgery at Brigham and Women’s Hospital in Boston, Massachusetts.
He noted that there are organ-specific ischemic times, as livers, for example, are less ischemia-resistant than kidneys. In addition, all organs are impacted by the quality and age of an organ, with older, comorbid organs less resistant to the consequences of ischemia and reperfusion injury.
“During reperfusion, all those aspects and components of the organ that have been damaged during the ischemic time are now activated and contribute to the damage of the organ after reperfusion. So, the reperfusion is necessary for the ischemic injury to kick in,” Dr. Tullius said.
As with any injury, ischemia-reperfusion initiates a potentially damaging inflammatory response—damage that can be particularly consequential in a transplanted organ. In kidneys and livers, ischemia-reperfusion injuries are associated with early graft dysfunction and eventual graft loss.2,3
Evolving Approaches Reduce Organ Damage Before Transplant
The damage that an organ experiences during this ischemic time can be prevented in part through various organ preservation and perfusion technologies, the optimal course for which differs by organ and available resources.
One of the most significant potential improvements for reducing ischemia and ameliorating reperfusion injury may involve increasing organ storage temperature.
Historically, most organs recovered as a donation after circulatory death (DCD) were transported and kept for use within static cold storage at a temperature of 4°C; however, while this option keeps metabolism to a minimum, evidence suggests this temperature may contribute to metabolic injury and restrict the time an organ is available to transplant.
Recent research and clinical evidence show that increasing the storage temperature to 10°C can reduce mitochondrial damage and other cellular degradation, improve organ function post-transplant, and increase the window for effective transplantation. While the most notable results have come in lung and heart transplants, emerging evidence suggests kidneys also may benefit from this approach.4
Beyond static cold storage, the greatest functional gains—or reduction in functional loss—are achieved through machine perfusion, which pumps oxygenated blood or nutrient solutions through organs to maintain their viability.
Hypothermic machine perfusion has been used for many years in kidneys, and more recently in livers, to reduce delayed graft function and early graft dysfunction, respectively. The most recent breakthroughs in organ functionality and longevity, particularly for livers, have occurred in normothermic machine perfusion (NMP) technology.
“With NMP, the DCD organs that surgeons were afraid to use for liver transplants because they came from medically complex donors or had long travel times and logistical challenges, are now becoming more usable,” explained Juliet Emamaullee, MD, PhD, FACS, a liver transplant surgeon and research director of the Transplant Institute at the University of Rochester Medical Center in New York.
“These technologies allow rehabilitation of organs to a certain degree, which mitigates potential injury to the bile ducts, for example,” she said, noting that NMP allows organs to maintain similar physiologic function outside of the body because they are maintained at body temperature.
With blood flowing through a normothermic pump, transplant teams also can evaluate the organ function by looking at liver function in real time—how it clears lactate, how it deals with glucose metabolism, and so on.
Dr. Emamaullee noted that there are two primary NMP providers offering their technology for liver transplants, one of which is a service-based model that includes a procurement surgeon and a perfusionist who travel with the device to a procurement site, procure the organ, and maintain it on the pump in transit to the recipient. The other machine is not service based and instead can be purchased by a transplant center or organ procurement organization (OPO) but requires specialized staff to operate the system.
There is an even more innovative normothermic approach to organ capture that forgoes an external machine—normothermic regional perfusion.
“This technique is used when you have a DCD donor who passes away, and then a team surgically places them on ECMO [extracorporeal membrane oxygenation]—but only for the abdominal or thoracic organs, without any blood supply to the brain,” Dr. Emamaullee said. “Clamps are applied to prevent cerebral blood flow so that a deceased donor is not reanimated like what might happen with CPR. You pump blood from the neck down, or from the diaphragm down to minimize injury to the organs.”
Both the external machine-based and ECMO-based normothermic approaches have shown favorable results for maintaining quality for donor organs and, ultimately, outcomes for the donor recipients.5,6
It should be noted, however, that these technologies are highly resource- and cost-intensive, potentially adding more than $80,000 to organ acquisition costs7—meaning their use is dependent upon available resources, which will limit potential access in a field in which disparities in access to care are visible challenges.
Clinical Advances Broaden Donor and Recipient Pools
The impact of these static cold storage or machine perfusion advances extends beyond adequately maintaining an ideal organ. They already are increasing the donor and recipient pool to include older individuals who may have had specific health issues such as diabetes or steatosis.
“Today, roughly half of kidneys from donors older than 55 are procured but not used for transplantation,” Dr. Tullius said.
With more than 90,000 individuals on the kidney waiting list in the US, raising that percentage even by only a few points could add thousands of organs to a strained system.
For liver transplants, the dramatic increase in DCD organ donation that is made possible by new perfusion technology—when and where available—is changing indications for transplant.
Dr. Turgeon (center) leads a kidney transplant.
“Because we have more organs available, our indications are expanding because it allows us to think more broadly about who we can transplant and still get good results,” Dr. Emamaullee said.
Alcoholic hepatitis is the newest, most expansive form of liver transplant indication, according to Dr. Emamaullee. Under the right circumstances, surgeons can offer a transplant to save the life of such a patient and provide a sustained, high-quality outcome, even if they haven’t achieved 6 months of abstinence and treatment through a rehabilitation program.
Patients with metastatic colon cancer that has spread to the liver also are now increasingly eligible for transplant if they meet a strict set of criteria.
In addition to improved storage that will lessen the metabolic and physiological degradation of any organ, there are medications and technologies that may allow for ex vivo organ reconditioning, Dr. Tullius said.
He noted a few promising rejuvenation strategies that may be “very close to a clinical reality”: senotherapeutic drugs, including senolytics that selectively remove senescent cells and senomorphics that inhibit inflammatory factors that senescent cells create, as well mitochondrial modulators that can enhance mitochondrial function that has lessened with age.8
Further in the future, stem cell therapies also may play a role in transplantation.
Policy Updates Aim to Grow Organ Supply, Improve Allocation
The supply side of the transplant system plays an important role in securing and allocating these extremely limited resources, and policy changes from the federal government, transplant centers, and OPOs are continuing to evolve.
The most foundational updates are likely to spring from efforts to modernize the Organ Procurement & Transplantation Network (OPTN), the public-private partnership that serves as a link between all transplant professionals in the US.
While the nation’s organ donation system has achieved significant success by growing access to the number of organs transplanted each year, the scale of data, regulations, and logistics presents opportunities to achieve even greater success.
The Securing the US Organ Procurement and Transplantation Network Act of 2023 modernized the OPTN by dividing its work from a single national contract into multiple vendors that specialize in different areas to improve patient safety, transparency, and equity, among other goals. The multiphase initiative is now in its third stage, and as of December 2025, most vendors had been selected.9
This modernization initiative is intended to allow for subject-matter expertise to have a greater impact within the transplant system. The United Network for Organ Sharing (UNOS), for example, will manage the OPTN’s matching system and data— a decision that may be particularly consequential for kidneys, as they are the organ that may be most sensitive to equity gaps.10
“In every policy we develop, we strive to create a fair, equitable, and efficient system that improves patients’ lives and honors the gift of life, and that is what we aimed to improve with the kidney allocation system,” said Nicole Turgeon, MD, FACS, a kidney and transplant surgeon, chief of the Division of Transplant Surgery, and a professor in the Department of Surgery and Perioperative Care at The University of Texas at Austin Dell Medical School.
Dr. Turgeon, who also is a past member and chair of the UNOS Kidney Committee and Policy Oversight Committee, described iterations of the OPTN kidney allocation system.
The “Kidney Allocation System 250” (KAS 250) was designed to provide a more standardized framework to improve equitable access to kidney transplants by eliminating local Donation Service Area (DSA) boundaries and promoting broader geographic sharing.
But even this system was constrained by geographic and socioeconomic realities. Therefore, the latest system reflects a shift toward reducing barriers in transplantation.
“The next iteration, ‘continuous distribution,’11 replaces rigid classification boundaries with a composite allocation score that prioritizes transplant candidates based on a weighted combination of medical urgency, biological compatibility, logistical efficiency, and other factors to improve long-term outcomes and reduce waitlist mortality,” Dr. Turgeon said.
When Logistics, Equity, and Public Perception Intersect
Because donor organs are such a visible and valuable resource, the transplant system is often highly scrutinized. And because organ transplantation is frequently perceived in binary terms—patients either receive a transplant and gain the possibility of extended, improved life, or they do not and may deteriorate or die while waiting. As a result, challenges in organ allocation policy that reach public attention underscore the importance of clear and equitable regulation.
Such was the case when The New York Times published an article in February 2025 with a provocative headline: “Organ Transplant System ‘in Chaos’ as Waiting Lists Are Ignored.”12 The longform piece described how patients who were at the top of their organ waitlist rankings were regularly passed over, while individuals hundreds or even thousands of spots below on the list were given organs.
Fairness is a common concern in organ allocation, and the article inflamed public and policymaker sentiment on an already sensitive topic. However, transplant surgeons and other medical experts saw this report on “out-of-sequence” allocation not as a failure of the transplant system, but a challenge to improve communication-related logistics. The response to the article also highlighted the importance of aligning standards related to transplant allocation.
“There are situations where we determine an organ is not a good match for a potential recipient. For example, an organ may not physically fit, or a patient may have multiple medical conditions that would make it physiologically intolerable to receive an organ that could take weeks to function properly,” Dr. Emamaullee said.
At the same time, surgeons want to ensure that every usable organ is transplanted. A transplant center might call the OPO they worked with to recover the organ, which could be several states away, and explain that the intended recipient is unable to move forward with this transplant. Sometimes these rare events happen after we have started the operation on the recipient. The organ has already been recovered and may have several hours of accumulated cold ischemic time.
“We may request that this organ is reallocated to the next appropriate recipient at our center because the process of them calling another center, seeing if their patient is ready, if they can accommodate it logistically—all of that just adds extra cold ischemic time. At some point the OPO must make a judgment call for an out-of-sequence or ‘expedited placement’ allocation to make sure the organ gets used,” she said.
Out-of-sequence allocation, then, is a tool that allows the organ transplant system to ensure organs are not wasted. Nevertheless, The New York Times article revealed regulatory gaps in the system that contributed to public misperception.
“The transplant system has evolved rapidly, achieving remarkable advances while creating opportunities to further strengthen coordination and consistency,” Dr. Turgeon said. “In policy development, we emphasize transparent, codified methodologies that enable impact assessment and the identification of unintended consequences, including disparities.”
Dr. Turgeon explained that transplant specialists recognize the need for a pathway to rescue organs, which would be allocation out of sequence, but it needs to be defined clearly, and those pathways need to be organized. While most organs allocated out of sequence are medically complex, there are some cases where organs were directed to centers that may have used them on patients closer to the top of ranking list. That, too, is largely based on easing the logistics of the transplant system, and never malicious intent.
“We are working to realign the system to balance equity, utility, and efficiency, facilitating the rescue of organs that might otherwise go unused and ensuring their allocation to centers with the capability to transplant them, rather than relying on pathways outside standard allocation processes,” Dr. Turgeon said.
Surgeons Must Continue to Lead
The ongoing work of addressing organ shortages has been making positive strides. By joining the expert-led committees in their hospitals, OPOs, or the OPTN itself, surgeons can use their clinical experience and research breakthroughs to bolster messaging regarding the importance of organ donation, both living and deceased, to policymakers and the public.
“Our field does an extraordinary amount of good, and there is always opportunity to improve,” Dr. Turgeon said. “While negative stories can draw attention, it is essential that we clearly communicate the facts and help the public understand the profound impact of organ donation and transplantation.”
Matthew Fox is the Digital Managing Editor in the ACS Division of Integrated Communications in Chicago, IL.
Khan S, Zuluaga D, Ratner LE, Cogua LM, et al. Emerging therapeutic strategies for renal ischemia-reperfusion injury in kidney transplantation: Progress and challenges-a systematic review. Clin Transplant. 2025;39(8):e70263.
Ito T, Naini BV, Markovic D, Aziz A, et al. Ischemia-reperfusion injury and its relationship with early allograft dysfunction in liver transplant patients. Am J Transplant. 2021;21(2):614-625.
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