Effects of hypothermic perfusion in isolated pig kidneys after warm ischemia

An experimental study in pigs was designed to evaluate the consequences of normothermic ischemia in hypothermic isolated renal perfusion (HP). We perfused 16 kidneys after 45 minutes of vascular occlusion. Another 16 kidneys were perfused without previous warm ischemia. The ureter was catheterized in all procedures and the output collected during HP. Creatinine was added to the perfusion solution initially in order to determine creatinine clearance (CrCl). HP hydrodynamics were recorded in real time through a computerized system. According to the results, renal vascular resistance as well as CrCl were higher in ischemic kidneys. Both facts, along with minimal differences in the microscopic study, suggested an increased vascular tone of the efferent postglomerular arteriole during HP. HP was proven to be an optimal technique to minimize the histological consequences of ischemia. Microvascular and biochemical changes produced during HP may be essentially related to dynamic causes.