Vessel Elasticity Rather Than Renal Parenchyma Determines Renovascular Resistance of Hypothermic Machine Perfusion.

Abstract

Background: Renovascular resistance (RR) of hypothermic machine perfusion (MP) is most important indicator of kidney viability, but the factors that affect RR remain unknown. Method: In the control clinical trial, two groups were divided according to whether delayed graft function (DGF) occurred, and the characteristics of RR were analyzed under different clinical scenarios. Rabbit models of renal interstitial fibrosis (RIF) and acute renal failure (ARF) were established to explore the affecting factors of RR. Results: Renal interlobular artery resistance index in the first 2 days after transplantation in DGF group were higher than that in Non-DGF group (P=0.002). RR in DGF group was higher (P<0.001). There was a DCD donor of chronic glomerulonephritis, RR of the left kidney with the lower expression of α-smooth muscle actin in vascular smooth muscle reached normal after 12 hr of MP while that of the right one with arteriosclerosis obliterans shown by HE stain could not. In the basic research, the RR of both the RIF and ARF rabbit in which the morphology of renal vessel was normal reached normal range after 4 hr of MP.Figure: No Caption available.Conclusion: RR is mainly affected by the vessel elasticity instead of renal parenchyma. RR could not imply the pre-existing lesions of renal parenchyma. Whether a kidney is transplanted or discarded can not be decided by RR alone.