[Combined use of mannitol and perfluorochemicals in experimental cerebral ischemia]

Using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump, the effects of mannitol (which acts as a free radical scavenger) and perfluorochemical emulsion (PFC, which has 0.1 micrograms of average particle size and a high oxygen-carrying capacity) on cerebral ischemia were investigated. After pretreatment with the drugs, blood flow was reduced via the pump to 1/10 of the normal flow volume and 1 hour later, return to a normal flow was allowed. Subsequent changes in electrical activity were observed and the effects of the drugs evaluated. In the control group, no recovery of electrical activity was seen, but in the animals treated with either mannitol or PFC, incomplete, yet distinct recovery was apparent. In the animals administered with mannitol together with PFC, however, marked recovery was evident. These experimental results indicated that a combined administration of PFC and mannitol is effective in protecting the brain from cerebral ischemia.