High oxygen extraction combined with extensive oxygen consumption in the rat liver perfused with Fluosol-DA a new perfluoro compound emulsion.

Different O2 values of the perfused rat liver and the metabolic turnover of urea and glucose, with and without substrate loads, were measured in a hemodiluted control group and in a group perfused with the perfluoro compound emulsion (PFC) Fluosol-DAR 1. The following results were obtained. The basal O2 consumption with PFC was 6.42 and 6.51 ml O2/(min·100 g liver), respectively, both being higher than in the control group, despite the fact that the latter revealed values of a good oxidative metabolism compatible with that found for larger species in situ. With substrate loads the values increased to a mean of 8.62 ml O2/(min·100 g) for periods of 20 min and more. Also O2 extractions of 95% could be found like otherwise mostly in cases with severely reduced O2 supply and under diminished O2 consumption. This seems to be due to the increased surface area of the O2 transporting particles with a mean diameter of 0.1 μm. Furthermore, the linear O2 delivery of physically dissolved oxygen from PFC enables a higher O2 pressure to remain in the outflowing perfusate after the same amount of oxygen is consumed, provided sufficiently high arterial O2 pressures are used. Finally, an increase of intracellular O2 concentration rather than O2 tension by incorporated PFC particles might play a role.—The substrate turnover values were compared with those in the literature; they are within the normal range.