Effect of dexamethasone on cerebral edema from cranial impact in the cat.

A Remington humane stunner was used to deliver blows to the skulls of anesthetized cats. Alternate animals were post-treated with either dexamethasone (4 mg/kg/day) or a comparable volume of saline. Each animal was tested for cerebral edema 48 hours after impact by measurement of the change in density of white matter from normal values. Dexamethasone therapy did not reduce the change in density of hemispheres with contusions involving both cortex and underlying white matter. For hemispheres with contusions limited to cerebral cortex, there was minimal edema of the white matter, which was reduced a slight amount by dexamethasone.