Recirculation in the acute period of cerebral infarction: experimental research on brain swelling and its suppression by using mannitol or glycerol.

Using our previously published "incomplete cerebral hemispheric infarction model in dogs" (produced by simultaneous ipsilateral occlusions of the anterior cerebral artery at the branching of the ethmoidal artery from its A1 portion, the A2 portion, the internal carotid artery, the posterior communication artery, the posterior cerebral artery, and the anterior cerebellar artery), two, four, or six hours occlusion of blood flow was undertaken. Observations were then made on the degree of brain swelling following recirculation due to administration of mannitol or glycerol solutions. Furthermore, the leakage of Evans blue was investigated to determine the damage to the blood brain barrier. 1. In the animals given mannitol or glycerol, brain swelling was suppressed, following two hours occlusion, In the animals given mannitol, however, brain swelling was not suppressed after four or six hours occlusion. 2. After two hours occlusion in the animals given mannitol, leakage of Evans blue was slight compared with the untreated group. In the six hours occlusion groups, severe leakage of Evans blue was seen in both the untreated animals and the mannitol-treated. After two hours occlusion, in some animals which had been given glycerol, severe leakage of Evans blue was seen, even when there was little brain swelling.