Modification of cerebral ischemia with Fluosol.

Abstract

Fluosol-DA (Perfluorochemical Blood Substitute) was investigated in a previous study and found to provide some protection from ischemia and possible usefulness in limiting the size of infarction. In the present study, larger doses over longer periods of acute focal cerebral ischemia were used. Twenty four cats had transorbital ligation of the middle cerebral artery (MCA). The 12 experimental animals were given 20% Fluosol-DA. The control group of 12 received isotonic saline solution. Twenty-four hours after the MCA occlusion, the cats were perfused with saline and phosphate-buffered formalin. The brains were removed and immersed in 10% formalin for 2 weeks. The results of macroscopic and histological examination suggested that, although Fluosol-DA did not provide complete protection from ischemic injury to the brains of the cats treated, it may have helped to slow the development of the pathological changes.

Effect of Fluosol on oxygen availability, regional cerebral blood flow, and infarct size in a model of temporary focal cerebral ischemia.

“…It is well-known that it takes several hours for ischemic cerebral edema to develop. 20 Indeed, in the study by Peerless and collaborators in which the cats were kept alive for 24 hours, 7 the beneficial effect of Fluosol was not as clear as in their earlier study 3 or in our acute study* where the animals were sacrificed within 6 hours from the onset of ischemia. It is also likely that reperfusion, even after only 2 hours of ischemia, had a deleterious effect by exacerbating brain edema.…”

“…4 "* In another study where cats were sacrificed 24 hours after occlusion of one middle cerebral artery (MCA), PFC also seemed of value although their effect was not as beneficial as in the acute experiments. 7 However, in a more "chronic" study where cats were treated either with PFC or with dextran and were kept alive for one week after a 4-hour period of MCA occlusion, we failed to show any benefit from either agent and there was a high mortality from cerebral infarction in both groups (unpublished data). We concluded that the 4-hour period of MCA occlusion followed by reperfusion in the cat is probably too severe an ischemic insult to allow the protective effect of any agent, if such effect was only moderate, to manifest itself.…”

Hemodilution for cerebral ischemia.

“…Fluorocarbon solutions were suggested as an ideal agent, and initial results in acute studies were very encouraging. 16 However, chronic studies in our laboratory have indicated that at least one of these substances, fluosol-DA, is not beneficial and may, in fact, be detrimental. 17 On the other hand, in our studies the infarction from MCA occlusion in cats was so large that there was a very high early mortality observed, and it is unlikely that a marginal therapeutic effect could have been noted.…”

19F Imaging of Cerebral Blood Oxygenation in Experimental Middle Cerebral Artery Occlusion: Preliminary Results

“…This may account for individual differ ences in the extent of infarction produced by exper imental MCA occlusion in cats (Kamijyo and Garcia, 1975). Additionally, spontaneous reperfu sion may have been facilitated by the perfluorocarbon exchange itself and the reduced viscosity and particle size of these emulsions (Peerless et a!., 1981(Peerless et a!., , 1985. Unlike the signal as ymmetry in the retia, the collaterals opened during occlusion per sist following clip release, perhaps owing to the presence of an endogenous vasodilator such as aci dosis (Lassen, 1966;Yamaguchi et a!., 1971).…”