Dexamethasone effects on the distribution of water and albumin in cold-injury cerebral edema.

To evaluate the effectiveness of steroids in the treatment of traumatic cerebral edema, we have hypothesized that the distribution of water and RISA is diminished by Dex and have experimentally tested this proposition with the rat model of cortical cold injury. Dex was found to have no effect on the water content of normal brain. The cold injury significantly increased the water content of only the right middle forebrain in untreated rats; in contrast, the increase in water content in the right middle forebrain after cold injury was small and insignificant in Dex-treated rats. Dex diminished the distribution of RISA in the tissue immediately adjacent to the primary lesion but did not affect RISA distribution within the lesion or the remainder of the brain. These findings suggest that steroids do not alter the distribution of water and albumin within cerebral tissue that has been heavily damaged and that steroids do affect these processes in the less traumatized tissue immediately surrounding the primary lesion.