Abstract:Currently, the main challenge faced by the global organ transplantation field is the shortage of donors. Due to a severe imbalance between the demand for recipients and the number of standard donors, surgeons have shifted their focus to donation after cardiac death (DCD). Compared to donation after brain death (DBD), DCD faces the major issue of experiencing a longer warm ischemia time (WIT), leading to an increased rate of postoperative complications in patients, particularly biliary complications. Controlled donation after cardiac death (cDCD) refers to a planned withdrawal of life-sustaining treatments following the wishes of the patients or their families. After a period of "no contact" (usually 5 min), the patient is declared permanently deprived of cerebral circulation while rapid organ recovery is performed. Since the transplantation of DCD donors preserved using conventional organ preservation methods is not satisfactory, the advantages of the normothermic perfusion technique have become increasingly evident during transplantation in recent years, garnering attention from surgeons and scientists. Unlike living liver transplantation and DBD liver transplantation, removing the transplant from a DCD donor is impossible before death is pronounced. However, during normothermic regional perfusion (NRP), surgeons can block blood flow to the brain after death is declared and initiate warm perfusion of the donor organ using extracorporeal membrane oxygenation. It restores the function of the donor liver in the donor body, allowing the liver to produce bile and remove lactate. This process provides valuable time to monitor and optimize the indicators of the donor's liver before it leaves the donor and is transplanted. Several clinical studies have already demonstrated that using NRP as an in-situ organ repair technique can yield transplantation outcomes for cDCD donor livers comparable to those of DBD donors. Additionally, some researchers have developed various combinations of perfusion techniques, including the use of NRP in conjunction with machine perfusion (MP) and dual hypothermic oxygenated machine perfusion (D-HOPE), all of which have shown promising transplantation results, offering more possibilities for liver transplant donor preservation. While many consider NRP a method of obtaining more high-quality organs, some scholars have raised ethical concerns about this technique. They argue that it violates the rules of donation after death and that the procedures involved in NRP perfusion may lead to the patient's death. Therefore, ensuring that the patient's circulation and respiration are irreversibly lost and that brain circulation is absent during NRP is particularly crucial. Given the importance of NRP in the field of transplantation, the authors provide a summary of the application of NRP techniques in cDCD.