Bowers, Dorrance

Evans blue dye was injected at a constant rate into the right ventricle or pulmonary artery of 17 subjects in 21 experiments. The consequent arterial dilution patterns were recorded continuously by a cuvette oximeter connected to an indwelling needle in the radial artery. From these dilution patterns the amount and concentration of dye in the intravascular space between the injecting and sampling sites were determined when an equilibrium concentration was attained. From these dimensions the "central vascular volume" was calculated. The values for the central vascular volume thus derived showed agreement with those determined in near-simultaneous estimations by Hamilton's modification of Stewart's method. The values for the "lung blood volumes" by the Newman method in these subjects were systematically smaller than the values for the central vascular volume.