An overview of the proposed biological applications of perfluorocarbons and their emulsions as oxygen-transport fluids is presented. 2. Aspects of the properties, preparation, composition and physiological assessment of perfluorocarbon emulsions are discussed. 3. The experimental basis for some of the potential therapeutic uses of PFCs in liquid ventilation, treatment of decompression sickness, organ perfusion, oxygenation of ischaemic and malignant tissues, and as contrast media for NMR imaging is described. 4. The extent to which emulsified perfluorocarbons may have value as substitutes for red blood cells is discussed in detail. Data from both animal and human studies with such emulsions is reviewed. Brief consideration is also given to the possible use of native and modified haemoglobin in blood replacement together with recent work on the preparation of so-called "synthetic red cells".
