Oxygen Tension of the Urine and Renal Structures

Early studies dating back to Claude Bernard demonstrated the extremely high oxygen saturation of blood in the renal vein (80 to 90 per cent) as compared to oxygen saturation of the venous return from other organs (50 to 70 per cent). It was therefore assumed that the renal parenchyma is richly endowed with oxygen and that renal hypoxia could rarely become a clinical problem.This approach to renal hemodynamics envisaged a rather homogeneous vasculature. It failed to recognize a complex vascular pattern within the renal parenchyma capable of allowing wide regional variations in blood flow and oxygenation under varying general . . .