Perfluoro compounds as artificial erythrocytes

Some liquid perfluoro compounds dissolve relatively large amounts of oxygen and can be used in dispersed form as substitutes for erythrocytes. The commonly used perfluoro compounds contain about the same amount of oxygen as do equal volumes of erythrocytes when equilibrated with 100% oxygen. However, when equilibrated with alveolar air, the perfluoro compounds contain much less oxygen than erythrocytes. The dispersed fluorochemicals are adequate substitutes for perfusion of isolated preparations of mammalian brain, heart kidney, lung and liver. However, when put into the circulation of the intact animal, the dispersed fluorochemicals tends to produce lesions of the lungs, dilation of the right heart, and ultimately fatal hypoxia. It is suggested that the course of events following intravenous injection of dispersed fluorochemical is initiated by an interaction of the perfluoro particles with blood platelets or blood clotting factors. The ensuing intravascular clotting could then cause the changes in the lungs which lead to a marked increase in pulmonary artery pressure and dilation of the right heart. These events would terminate in fatal hypoxia due to pulmonary pathology and heart failure.