Near Total Blood Exchange with Perfluorochemical Preparations

Near total blood replacement in rats has been accomplished with perfluorochemical (PFC) preparations containing hydroxyethylstarch and electrolytes. F-dimethyladamantane (F-DMA) was used alone or mixed with F-N,N-dimethylcyclohexylmethylamine (F-CHA). These compounds were emulsified to yield particles approximately 150 to 250 nanometers in diameter. The nonionic surfactant, Pluronic F68, was used as the emulsifying agent. Over ninety percent of the rats survived when their hematocrits were taken to 3 volume percent or lower from a pre-perfusion value of about 44 volume percent. In spite of the reduction in total mixed venous oxygen concentration, the oxygen partial pressure rose. During the perfusion the rats breathed 100 percent oxygen, but during the subsequent period this was decreased 10 percent per day. Six to 7 days later the hematocrits had risen to 30 to 40 volume percent. Thereafter the animals continued to develop and grow.