Organ Transplant Trends

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Organ Transplant: Trends

The use of paired kidney exchange, split-liver transplant, and ventricular assist device are some innovations surrounding the US organ transplant. Also, there has been a dramatic increase in the number of organ transplants for people with damaged livers rising from alcoholism since 2013.

TRENDS/INNOVATIONS IN ORGAN TRANSPLANT

PAIRED KIDNEY EXCHANGE

  • The use of AI in paired kidney exchange is a technological innovation transforming the US organ transplant, and it's on the rise at multiple hospitals.
  • The technology uses algorithms to weigh different criteria, including the recipient's age, the length of time he or she has been on the waiting list, and if the person was once an organ donor, among others, to match patients getting first priority with biologically suited donors.
  • This trend has been on the increase since 2002 with about 0.2% of living donations from paired donors to 12% in 2018.

USING INFERIOR ORGANS

  • Researchers are inventing new ways to recover and use organs that would normally be rejected.
  • Every year, 1,000 donor hearts are discarded due to hepatitis C infection in the US. The advancement in treatment breakthroughs has allowed doctors and researchers to experiment with hepatitis C infected organs for transplantation.
  • For example, at Penn Medicine in Philadelphia, doctors are using hepatitis c-infected hearts and kidneys for transplant and later giving recipients drugs to clear the disease.

SPLIT-LIVER TRANSPLANT

  • The use of split-liver transplant, a technique that uses one deceased donor liver for two people, is another innovation surrounding the US organ transplant.
  • This technique is made possible since the liver is the only organ able to regenerate and replace damaged tissue with new cells.
  • Medical College of Wisconsin is among a few hospitals in the US using this method to transplant liver.
  • Nearly 2 percent of liver transplants in the US employ split-liver transplant "because it requires the highest level of expertise and care."

VENTRICULAR ASSIST DEVICE (VAD)

  • Some hospitals in the US are using a unique innovation, Ventricular assist device (VAD) that pumps blood from the heart to the body of a transplant recipient waiting for a donor heart to become available.
  • The devices can be "used as a bridge to transplant, or, for people who are not good transplant candidates."
  • Froedtert Health uses VAD to help prolong the life of its heart failure patients while they are waiting for a heart transplant.

INCREASED-RISK ORGANS

  • There's been a rise in 'increased-risk' donor organs in the United States.
  • Increased-risk organs are from persons who either injected drugs, had sex for drugs, or were incarcerated.
  • Unfortunately, patients in the wait list are rejecting these organs, which account for one in every five deceased donor organs today, despite disease transmission being low. This has lead to "hundreds of available organs going unused each year."

ALCOHOLIC LIVER DISEASE (ALD)

  • The number of organ transplants for people with damaged livers as a result of alcoholism has dramatically increased since 2013, representing an increase of 177 per year.
  • There were a "stable number of ALD transplants per year" between 2002 and 2012.
  • In 2016, ALD became the "leading indication for wait list additions (30%)," with the trend continuing in 2017.

RESEARCH STRATEGY

The research team examined medical databases such as NCBI, Science Direct, Journal of Hepatology, Science Daily, and many others to identify six trends and innovations surrounding the US organ transplant. We selected trends that indicate an upward change in the past decade, have more health organizations participating, and recent unique innovations that are expert-backed to be novel.
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Organ Transplant: HMP vs. SCS

Hypothermic machine preservation (HMP) decreases the risk of delayed graft function (DGF) and failure in deceased donor organ. In static cold storage (SCS), prolonged storage of deceased organ past 24 hours leads to tissue damage, limited opportunity for transplant, and assessing donor organ function.

Static cold storage (SCS)

  • Static cold storage is a form of organ preservation where the organ (kidney or liver) is "stored on ice after removal from the donor and then removed from the icebox at the time of implantation." The cold environment enhances the activities of anaerobic metabolism and lactic acidosis while reducing metabolic activity by ten times, thus protecting the organ from damaging.
  • Multiple studies reveal that static cold storage is limited by time, as prolonged cold storage depletes energy stores and reduces cell function in deceased organ as a result of continuous metabolic activities, leading to poor post-transplant function after 24 hours of preservation.
  • Preservation with SCS is associated with the following limitations to the organ: "tissue damage induced by prolonged hypothermic preservation, difficulty in assessing donor organ function and viability, the inevitability of ischemia-reperfusion injury (IRI), and limited opportunity for organ repair."
  • In the case of static cold storage, as opposed to other methods, the organ procurement organization (hospital or health organization) is responsible for the donor organ as it is transported to the transplant center and removed from sterile packing. If the transplant center (also a hospital) performs perfusion, it assumes potential liability if the organ is contaminated or injured regardless.
  • Static cold storage is recognized as the "gold standard preservation for standard-criteria livers" with good long-term patient survival. However, with an increase in demand from the overall transplant population, lower-quality organs are used — made possible by the introduction of HMP.

Hypothermic machine preservation (HMP)

  • Hypothermic machine perfusion (HMP) drives dynamic cold solutions at 4 degrees Celsius through donated organs to ensure the "homogeneous and continuous supply of metabolic substrates" to the organ graft during the ex vivo period. Ex-vivo is the process of growing cells outside the living system. The aim is to "decrease the damage done during transport and therefore improve the outcomes for these organs" prior to transplantation.
  • Hypothermic machine perfusion reduces the rate of graft failure and delayed graft function, by approximately 23%, in deceased donor organ when compared to static cold storage.
  • A hospital using HMP to preserve kidneys is likely to notice overall cost savings "of $86,750 per life-year gained."
  • For patients, there's evidence that preservation with hypothermic machine perfusion "prolongs the length of time that donated organs (kidneys) survive in the recipient," but it makes "little or no difference in the survival of the patient."
  • Hypothermic machine perfusion is also useful in drug delivery, the delivery of "potentially protective therapies to the kidney during preservation without systemic administration."
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