Value of Continuous Photoelectric Recording of Dye Curves in the Estimation of Cardiac Output

In order to test photoelectric recording of dye curves, simultaneous determinations of cardiac output were made in 48 patients with heart disease with the Fick and dye-dilution technics. The dye curves were recorded with a Colson densitometer following either intrathoracic or antecubital injection of dye. Both Evans blue and indocyanine green dyes were employed. Satisfactory agreement was noted between Fick and dye estimates, demonstrating empirically the usefulness of the continuous recording technic.