THE PERFLUOROCARBON FLUOROMETHYLOADAMANTANE OFFERS CEREBRAL PROTECTION IN A MODEL OF ISOVOLEMIC HEMODILUTION IN RABBITS

Background and Purpose Perfluorocarbons (PFCs) are considered promisin g cerebral protection agents because they could combine the beneficial effects of decreased blood viscosity with enhanced oxygen-carrying ca pacity and oxygen tissue delivery, but trials of PFCs as hemodilutants have been very limited. We evaluated fluoromethyloadamantane (FMA), a new perfluorocarbon compound, as an isovolemic hemodilutant and compa red it with low-molecular-weight dextran 40 (D40) and a control group. Methods Through a transorbital craniectomy, the internal carotid, ant erior, and middle cerebral arteries were coagulated to create a cerebr al infarction in anesthetized, mechanically ventilated rabbits. No oth er experimental procedure was performed in control animals. In the two other groups, hemodilution was commenced 30 minutes after the arteria l occlusion with either D40 or FMA. Hemodynamic parameters and brain a nd systemic temperature were monitored throughout the experiments. All animals were killed 6 hours after the arterial occlusion. Results Hem odynamic and metabolic parameters and blood oxygen content were not af fected by the infusion of either FMA or D40. Brain and systemic temper ature remained constant. The ratio of infarct volume to the hemispheri c volume was 19.6+/-3.7% in the FMA group (n=17), 19.9+/-4.6% in the D 40 group (n=16), and 40.3+/-5.7% in the control group (n=17). The diff erence in infarct volume of both FMA and D40 animals compared with con trols was statistically significant (P<.01) when tested with Student's t test. There was no significant difference between FMA and D40 group s. Conclusions These results suggest that FMA has cerebral protective properties and should be purified, optimized, and further tested exper imentally to develop a stable, efficient, and safe oxygen carrier, pot entially suitable for clinical trials.