Negative impact of prolonged cold storage time before machine perfusion preservation in donation after circulatory death kidney transplantation.

Kidney grafts are often preserved initially in static cold storage ( CS) and subsequently on hypothermic machine perfusion ( MP). However, the impact of CS/ MP time on transplant outcome remains unclear. We evaluated the effect of prolonged CS/ MP time in a single-center retrospective cohort of 59 donation after circulatory death ( DCD) and 177 matched donation after brain death ( DBD) kidney-alone transplant recipients. With mean overall CS/ MP times of 6.0 h/30.0 h, overall incidence of delayed graft function ( DGF) was higher in DCD transplants (30.5%) than DBD transplants (7.3%, P < 0.0001). In logistic regression, DCD recipient ( P < 0.0001), longer CS time ( P = 0.0002), male recipient ( P = 0.02), and longer MP time ( P = 0.08) were associated with higher DGF incidence. In evaluating the joint effects of donor type ( DBD vs. DCD), CS time (<6 vs. ≥6 h), and MP time (<36 vs. ≥36 h) on DGF incidence, one clearly sees an unfavorable effect of MP time ≥36 h ( P = 0.003) across each donor type and CS time stratum, whereas the unfavorable effect of CS time ≥6 h ( P = 0.01) is primarily seen among DCD recipients. Prolonged cold ischemia time had no unfavorable effect on renal function or graft survival at 12mo post-transplant. Long CS/ MP time detrimentally affects early DCD/ DBD kidney transplant outcome when grafts were mainly preserved by MP; prolonged CS time before MP has a particularly negative impact in DCD kidney transplantation. [ABSTRACT FROM AUTHOR]