Optimal donor organ preservation conditions: methods, preservation time and outcomes From machine perfusion preservation in clinical kidney transplantation to experimental liver cell preservation.

This thesis focuses on the duration of organ preservation times and explores the limits of cold ischemia time (CIT). Clinical outcomes after kidney transplantation from different donor types, preserved using either static cold storage (SCS) or hypothermic machine perfusion (HMP), were included in the studies. The results show that prolonged CIT does not necessarily pose a problem when kidneys from deceased brain-dead (DBD) donors are used in combination with HMP. Warm ischemia time (WIT), which category 3 donation after circulatory death (DCD) donor kidneys undergo after circulatory arrest, was found to reduce the allowable limit for CIT.
Hemodynamic instability during the functional WIT phase, also known as the agonal phase, may contribute to the undesirable effects of the initial WIT. The thesis analyzed hemodynamic parameters and their predictive value for outcomes after kidney transplantation. It shows that a systolic blood pressure < 80 mmHg during the agonal phase is a better discriminator for transplant outcomes than SpO2 < 60%.
The second part of the thesis explores the optimal preservation solution for experimental liver endothelial cell preservation. We found that the inhibitory IgG receptor, FcγRIIB, was highly expressed on liver sinusoidal endothelial cells (LSEC). Furthermore, we discovered that EGM2 and UW preservation solutions were the most effective at maintaining the cellular integrity and barrier function of LSEC.