Clearance and Non-Invasive Determination of the Hepatic Extraction of Indocyanine Green in Baboons and Man

Abstract

The disposition of an i.v. bolus of indocyanine green (ICG) was studied in healthy man and [Papio] baboons using a novel analysis of a 2 compartment pharmacokinetic model. This analysis enabled the hepatic extraction ratio (ER) of dye to be determined solely from the plasma disappearance curve, and the ER determined did not differ from that measured by hepatic vein catheterization. When compared with clearance measured at steady state, the 2 compartment model gave a significantly more accurate determination of plasma clearance than did the conventional one compartment model. In health, liver blood flow may be calculated accurately and noninvasively after a single i.v. injection of ICG.