Triphasic response of glomerular filtration rate after experimental brain death in pigs

Abstract

Background Clinical outcome after transplantation of kidneys derived from deceased brain death (DBD) donors is inferior compared to living donor kidneys. In this observational model, the effect of experimental brain death on renal function was evaluated. Furthermore, we tested the effect of DBD transplantation on inflammation and renal metabolism in donors and recipients. Methods Eight Danish landrace pigs served as DBD donors. After four hours of brain death, kidneys were removed and stored for 19 hours at 4°C in Custodiol®. Next, the donor kidneys were transplanted into eight recipients. Glomerular filtration rate (GFR) was determined as urinary clearance of 51Cr-EDTA. Results Immediately following brain death, GFR and urine output were reduced while during the second hour hyperfiltration was observed. Subsequently, GFR and urine output decreased again. No systemicor renal inflammation was observed in the donors, while in recipients only renal inflammatory markers were increased ten hours post-reperfusion. Furthermore, mitochondrial dysfunction tended to develop after reperfusion. Conclusions In conclusion, brain death caused a triphasic response of GFR. No systemic inflammation in brain death donors was observed probably due to active control of hemodynamics by fluid administration. These new insights in the effects of brain death may inspire development of new strategies to improve outcome of DBD kidney transplantation.