Perfluorochemical Artificial Blood as a Volume Expander in Hypoxemic Respiratory Failure in Dogs

Abstract

The perfluorochemical O2-transport fluid, Fluosol-DA 20 percent (PFC), is being clinically evaluated as a volume expander in patients who are unable to receive blood products. Since patients treated with Fluosol-DA may be at risk of developing adult respiratory distress syndrome (ARDS) as a complication of the original disorder for which they were transfused, we examined central hemodynamics and gas exchange in anesthetized O2-ventilated dogs with oleic-acid induced pulmonary edema before and after transfusion with 400 ml of either PFC (n = 5) or whole blood (n = 5). Transfusion produced similar increases in cardiac output, pulmonary and systemic vascular pressures and intrapulmonary shunt in the two groups. Arterial O2 tension, however, fell from 209 +/- 117 to 172 +/- 81 mmHg in the blood transfused group but increased from 219 +/- 145 to 302 +/- 138 mmHg in the PFC group. Arterial O2 content, on the other hand, increased in the blood transfused group due to an increase in hematocrit, but fell with PFC because of hemodilution. This lower total arterial O2 content in the PFC group was, however, compensated for by more efficient O2 transport by the PFC in that the PFC arteriovenous O2 content difference accounted for 26 percent of the total arteriovenous O2 content difference, making it about four times as efficient as hemoglobin in tissue O2 delivery. Fluosol DA, 20 percent, is an effective volume expander in this model of hypoxemic respiratory failure, and it can transport significant amounts of O2 even in the presence of a substantial intrapulmonary shunt.