Blood gas transport of fluorocarbon emulsion and its effect on the metabolism in peripheral tissue

The effects of fetal exchange transfusion with a red blood cell substitute

Isovolemic exchange transfusion in the fetal lamb in utero was performed with the use of Fluosol-DA (20%), a perfluorochemical erythrocyte substitute. With maternal hyperoxygenation, a physiologic PO2 was maintained in the fetal lambs, although the total fetal oxygen content decreased as the hematocrit dropped. Because of the oxygen-carrying properties of the perfluorochemical emulsion, the fraction of fetal oxygen carried in the dissolved state increased significantly when compared with that in controls that received saline solution.

Steroid secretion by rat testes perfused with perfluorochemicals as oxygen carriers

Organs perfused in vitro are important experimental models for physiological studies. Perfusion medium supplemented with artificial oxygen carriers would at physiological flow rates supply sufficient oxygen to organs and would be superior to medium containing erythrocytes because it is more defined. Perfluorotributylamine (FC-43), a perfluorochemical, is an artificial oxygen carrier that has been previously reported to be ineffective in maintaining endocrine organs perfused in vitro. The purpose of this study was to determine the efficacy of FC-43 as an oxygen carrier for rat testes perfused in vitro. The effects of FC-43 on testicular function and structure were assessed by comparing the results of experiments using perfusion medium containing either FC-43 or erythrocytes. The results suggest that perfusion medium containing perfluorochemicals must be prepared by standardized procedures and defined as to its physiochemical parameters. The study resulted in the first successful in vitro perfusion of an endocrine organ with perfluorochemicals as oxygen carriers. The results not only provide the basis for an improved perfusion medium but also support in vitro perfused testes as effective experimental tools for testing perfluorochemical-based blood substitutes.

Electron microscopy findings in fetal organs after perfusion of the amniotic cavity with oxygenated fluorocarbon

In 20 fetal rabbits a double-blind electron microscopy study of placenta, lung, heart, liver, and stomach was performed at 28 or 29 days of gestation. The amniotic cavity was continuously perfused with perfluorotetrahydrofuran (FC 77) before the fetuses were killed. Compared with control fetuses, no morphological changes of fetal lung and stomach nor of placenta related to FC were found. There were unexplained changes in liver parenchymal cells. However, a protective effect of FC on the myocardial tissue was observed.

[Is there a possibility of paraplacental oxygenation of fetal blood? First results of an investigation with fluorocarbon (author's transl)]

By checking the cardiotropic effect on fetal rabbits we tried to find out weather there is a possibility of paraplacental oxygenation of fetal blood. Amniotic caves of nine fetal rabbits of 28th or 29th day of gestation are perfused with Perfluorobutyltetrahydrofuran (FX 80, 3 M Comp., St. Paul, Minn., USA) continuously. This was done by double blind investigation. The fetal heart rate is written by Hewlett-Packard-cardiotocograph. Therefore we use modificated EEG-electrodes. 48 h before we cut the spinal cord of the pregnant animals just for analgesie. So we exclude the influence of analgesics or narcotics. After complete interruption of uterine blood supply you can find an initial reduction of fetal heart rate. Using fluorocarbon we notice an increasing or stabilisation of fetal heart rate of all rabbit fetus. In comparison with control animals the difference is high significant. The cardial survival rate of four fetal rabbits treated with fluorocarbon is prolonged up to 50 min. During this time all "fluorocarbon fetus" never died earlier than the control animals. Lots of new questions are provoked by our results. One has to find an answer.