Determination of regional and central circulation times by the ascorbate dilution method.

The usefulness of the ascorbate dilution method in demonstrating intracardiac shunts and valvular incompetence is known. The ascorbate technique can also be applied to the determination of the transit time of regional vascular beds such as the coronary and the renal systems. Furthermore, the determination of central circulation times may be helpful in the diagnosis of caval obstruction. The method is safe, simple, inexpensive, and reliable.