Measurement of cardiac output by thermal dilution in man.

Abstract

This technique is most useful during acute disturbances of circulation. A thermistor mounted at the tip of a miniature cardiac catheter is floated into the pulmonary artery, and temperature change is recorded following the injection of room temperature saline or dextrose through a catheter in the internal jugular vein. Correlation with the direct Fick technique gives highly significant results. The method is particularly valuable where serial measurements at short intervals are required because the result is available immediately. Cannulation of the internal jugular vein has a much wider application than the measurement of cardiac output.