Perfluorocarbon emulsion improves oxygenation of the cat primary visual cortex

Tissue PO₂ was measured in the primary visual cortex of anesthetized, artificially ventilated, normovolemic cats to evaluate the effect of small doses [1 g perfluorocarbon (PFC)/kg] of a PFC emulsion (1 g PFC/1.1 ml emulsion Alliance Pharmaceutical, San Diego, CA) on brain oxygenation. The change in tissue PO₂ (ΔPO₂), resulting from briefly changing the respiratory gas from room air to 100% oxygen, was measured before and after intravenous infusion of the emulsion. Before emulsion, ΔPO₂ was 51.1 ± 45.6 Torr (n = 8 cats). Increases in ΔPO₂ of 34.0 ± 26.1 (SD) % (n = 8) and 16.3 ± 8.4% (n = 6) were observed after the first and second emulsion infusions, respectively. The further increase in ΔPO₂ after the third dose (7.9 ± 10.5% n = 7) was not statistically significant. The observed increases in tissue oxygenation as a result of the PFC infusions appear to be the result of enhanced oxygen transport to the tissue.