Cerebral function during profound oligemic hypotension in the dog

Abstract

✓ Electrocortigraphic activity and common carotid blood flow were studied in 12 dogs during and following profound oligemic hypotension. Five animals survived but seven died within 75 min of hypotension. Although an 80% to 90% reduction in both mean arterial pressure and common carotid blood flow was observed, only a 20% diminution of intracranial pressure occurred and there was little change in electrocorticographic function. The preservation of cerebral function in the presence of profound systemic hypotension was demonstrated. When death occurred during shock, no prior change in central nervous system function was noted. With reinfusion, no change in parameters was noted, but common carotid blood flow was depressed to 35% to 50% of control levels for up to 2½ hrs of observation.