Liver transplantation

What is Liver Transplantation and Why Is It So Important?

Liver transplantation or hepatic transplantation is the replacement of a diseased liver with a healthy one from another person for end-stage liver disease and acute liver failure. This procedure can be life-saving, but it comes with its own set of complexities. Have you ever wondered how such a critical organ can be replaced, and what makes this surgery so vital?

The Process Behind Liver Transplantation

Medical uses include treatment for acute or chronic conditions causing irreversible and severe liver dysfunction. The outcomes are highly variable, making each case unique. Clinical scoring tools like the Model for End Stage Liver Disease (MELD score) and Pediatric End Stage Liver Disease (PELD score) help assess the need for a transplant. But what exactly does this process entail?

Risks and Complications of Liver Transplantation

Risks/complications include graft rejection, which can occur in three types: hyperacute, acute, and chronic rejection. Hyperacute rejection happens within minutes to hours after the transplant procedure due to preformed anti-donor antibodies. Acute rejection involves T cells and may present with lab findings such as elevated liver enzymes and abnormal blood glucose levels. Chronic rejection occurs years later. Biliary complications include stenosis, leak, and ischemic cholangiopathy treated with ERCP, percutaneous drainage, or re-operation. Vascular complications like thrombosis, stenosis, pseudoaneurysm, and rupture of the hepatic artery can also arise.

Living Donor Liver Transplantation: A Lifesaving Option

Before transplantation, liver-support therapy might be indicated. The transplant operation is done orthotopically through a large incision in the upper abdomen, involving division of ligaments and blood vessels. Implantation involves anastomoses of inferior vena cava, portal vein, and hepatic artery. This surgery usually takes 5-6 hours. Living donor liver transplantation (LDLT) has emerged as a critical surgical option for patients with end-stage liver disease due to the shortage of cadaveric livers. LDLT involves surgically removing a healthy portion of the liver from a living donor and transplanting it into a recipient.

Donor Requirements and Evaluation

Donors must be in good health, have compatible blood type (although some centers perform incompatible transplants), be between 20-60 years old, and have a personal relationship with the recipient. Before becoming a living donor, individuals must undergo testing to ensure physical fitness and excellent health.

Post-Transplantation Care and Long-Term Outcomes

Liver transplant prognosis varies depending on overall health, surgery success, and underlying disease process, with a 58% survival rate after 15 years. Failure of the new liver (primary nonfunction) occurs in 10-15% of cases, often due to preexisting disease or technical flaws during surgery. Post-transplant immunosuppression requires medications such as corticosteroids, calcineurin inhibitors, and purine antagonists to prevent rejection. Vaccinations are highly recommended before and after liver transplantation due to the risks of chronic rejection and reduced vaccine effectiveness post-surgery.

The Evolution of Liver Transplantation

The first liver transplants were performed on dogs in 1954, followed by the first human transplant in 1963 by Thomas Starzl, who died after attempting it. However, subsequent attempts led to the development of viable surgical techniques, and the introduction of ciclosporin improved patient outcomes in the 1980s. Living donor liver transplantation was developed due to a shortage of liver allografts from non-living donors, with the first altruistic living donation performed in Britain in 2012. Many famous individuals have received liver transplants, including athletes, musicians, actors, and politicians, who survived for varying lengths of time.

Advancements in Liver Transplantation

Research is ongoing to improve methods for allograft preservation, including machine perfusion and cold storage techniques. Graft survival and patient survival after transplant were similar with both approaches. Machine perfusion prior to transplant is associated with decreased tissue re-perfusion ischemic injury as well as a decreased risk of intrahepatic biliary strictures. Normothermic Regional Perfusion (NRP) has shown promising results in DCD organ transplantation, particularly in kidney and liver transplantation, with lower rates of complications and improved graft survival compared to traditional preservation methods. NRP can be established either abdominally or thoracoabdominally, depending on the intended organs for transplantation.

Controversies and Ethical Considerations

The eligibility of patients with alcoholic cirrhosis for liver transplant is a controversy, as alcoholism is viewed as a self-inflicted disease. However, patients who have controlled alcohol use disorder are considered more deserving candidates. Historically, HIV was an absolute contraindication to liver transplantation, but highly active antiretroviral therapy (HAART) has improved prognosis for people with HIV. Uncontrolled HIV disease remains an absolute contraindication. Medical criteria often require ‘lack of substance abuse,’ including medical cannabis use. The changing status of cannabis has led to patients being denied transplants or forced to stop a useful medicine, despite never abusing the substance.

In conclusion, liver transplantation is a complex and life-saving procedure that requires careful consideration of various factors. From the initial screening process to post-transplantation care, every step plays a crucial role in ensuring successful outcomes. As medical advancements continue, we can only hope for more effective treatments and better patient experiences.