What are orthotopic procedures

Liver Transplant - Procedure and Technique

After the first liver transplants on humans in the 1960s, the technique of liver transplantation has been continuously developed. The methods currently in use are presented in the following overview.

Orthotopic liver transplantation with a postmortem donated whole organ is the original transplantation technique as developed by Dr. Tom E. Starzl was described and performed for the first time in the USA, and is still the most common transplant technique in Germany and worldwide.

 

After completion of the brain death diagnosis and determination of the irreversible failure of the overall brain function as well as after checking the suitability and consent of the organ donor or his family, the liver (and possibly other organs) is explanted as part of the organ removal and transported to the transplant center of the recipient selected by EUROTRANSPLANT.

In the transplant of the recipient with liver disease, the first step is to remove the diseased liver from the right upper abdomen (Hepatectomy) and prepare the blood vessels and bile duct for the connection of the new liver.

When the liver is removed, as in the original, Starzl described "conventional technology“, Which also removes the inferior vena cava, which is closely connected to the diseased liver. Until the new organ has been implanted (with a corresponding new vena cava), a machine blood bypass can be created to divert the blood to the inferior vena cava.

In a second step, the new liver is removed from the ice cooling and transplanted into the place of the removed diseased liver. For this purpose, the blood vessels supplying the liver (artery, portal vein, vein) and the bile duct must be connected to one another.

Alternatively, hepatectomy can preserve the inferior vena cava. To do this, the diseased liver must be carefully dissected from the vena cava. The transplant with its own vena cava is then carried out using a so-called "piggyback technique" ("piggy-back technology ") connected to the recipient's vena cava. Maintaining the vena cava is usually more difficult technically, but because of the preserved blood flow it is less of a strain on the circulation for the recipient. Whether the transplant is carried out using the conventional or the piggy-back technique must be decided individually for each patient.

Liver transplantation using a whole organ from a deceased donor offers several advantages. Since it is a complete organ with completely preserved blood vessels and bile duct, the transplant is sufficiently large and the implantation is technically easier than with a partial organ. Disadvantages, among other things in view of the aging organ donors, are the sometimes impaired organ quality as well as the so-called cold ischemia time, during which the organ (with cooling and without blood circulation = cold ischemia) sometimes has to be transported over long distances from the removal hospital to the transplant center.

The split liver transplant was developed in 1988 by Rudolf Pichlmayr at the Hannover Medical School. With "splitting" a donor liver of a deceased donor is divided in such a way that a recipient can be transplanted with each part of the liver. As a rule, part of the left lobe of the liver (so-called "Left lateral split") used to transplant a toddler and the remaining enlarged right lobe of the liver to care for an adult recipient. In rare cases, the liver can also be divided in its anatomical center (so-called. "True split") and two adolescent or physically smaller adult patients are transplanted with both liver lobes.

Technically, the liver division can be carried out in the body of the deceased donor before the organ is removed (so-called. "In-situ split") or after removal and started cooling outside the body in the ice water bowl (so-called. "Ex situ split") can be made.

Split liver transplantation has the obvious advantage of transplanting two recipients with one donor liver. However, only organs of good organ quality can be considered for splitting. Since each recipient must be supplied with a certain minimum amount of liver, depending on their body size and weight, a careful selection of the recipient according to the size of the partial liver is particularly important for the success of the split transplant. Since the main blood vessels and bile ducts of the liver are simply created and can only stay on one side during division, the implantation of the liver part without the corresponding main vessels requires special surgical expertise.

In the case of living liver donation, a part of the liver is transplanted into a patient with liver disease that was previously removed from a living donor. Living liver donation was developed in the late 1980s to remedy the incipient lack of organs, particularly in the area of ​​child transplants. The first reports of living liver donations for transplants from childhood patients came from Silvano Raia in Brazil, Russel Strong in Australia and Christoph Broelsch in the USA, while the first living donations from adult recipients were made by Yasuhiko Hashikura in Japan and Chung-Mau Lo in Hong Kong. Living donation is of particular importance in Southeast Asia and accounts for more than 90% of all transplants there, as organ donation from deceased donors rarely occurs for cultural reasons.

To transplant a child, part of the left lobe of the liver is removed from an adult donor. An adult patient transplant requires a larger graft, either the right or left lobe of the liver. As already mentioned in the section “Split liver transplantation”, a particularly careful selection of donor and recipient is essential for the success of a transplant with a partial liver.

Living donation gives a patient with liver disease the chance of a prompt transplant at the price of a risk-free operation on a healthy person. In contrast to the transplantation of organs from deceased donors, which are always emergency interventions, living donations can be planned in time with both operations. Donors and recipients can be optimally prepared for the operation. Since the removal and transplantation are usually carried out in parallel or immediately after one another, the cold ischemia time mentioned is very short. As a transplant of a part of the liver, living donation harbors the same technical risks that have already been addressed in the section entitled “Split liver transplantation”. With the appropriate selection of donors, however, an excellent quality of the transplant can be ensured.

 

In Germany, the legal provisions on living donation are set out in Section 8 of the Transplantation Act.


Last update: 29.11.2018