Timing of Kidney Clamping and Deceased Donor Kidney Transplant Outcomes.

Background The recognition that metabolism and immune function are regulated by an endogenous molecular clock generating circadian rhythms suggests that the magnitude of ischemia-reperfusion and subsequent inflammation on kidney transplantation, could be affected by the time of the day. Methods Accordingly, we evaluated 5026 first kidney transplant recipients from deceased heart-beating donors. In a cause-specific multivariable analysis, we compare delayed graft function (DGF) and graft survival according to the time of kidney clamping and declamping. Participants were divided into clamping between midnight and noon (AM clamping group, 65%) or clamping between noon and midnight (PM clamping group, 35%), and similarly, AM declamping or PM declamping (25% / 75%). Results DGF occurred among 550 participants (27%) with AM clamping and 339 (34%) with PM clamping (adjusted OR = 0.81, 95%CI: 0.67 to 0.98, p= 0.03). No significant association of clamping time with overall death censored graft survival was observed (HR = 0.92, 95%CI: 0.77 to 1.10, p= 0.37). No significant association of declamping time with DGF or graft survival was observed. Conclusions Clamping between midnight and noon was associated with a lower incidence of DGF whilst the declamping time was not associated with kidney graft outcomes.