Preconditiong With Hyperbaric Oxygen Attenuates Brain Edema After Experimental Intracerebral Hemorrhage

Objective To investigate preconditioning with hyperbaric oxygen on brain edema and inflammation after intracerebral hemorrhage, and study the mechanism of brain injury after intracerebral hemorrhage.Methods 60 male Sprague-Dawley rats received an intracerebral injection of 100μL autologous blood. They were randomized into model group receiving three, five, or seven consecutive sessions of preconditioning with HBO (3 ata,100% oxygen,1 hour daily) and control group receiving normobaric room air. Parts of rat brains were decapitated 24 hours or 72 hours after ICH to measure brain water; parts of rat brains were removed 24 hours or 72 hours after ICH to measure inflammatory reaction.Results Fewer than five sessions of preconditioning with HBO did not significantly attenuate brain edema 24 hours after ICH. Five sessions of preconditioning with HBO reduced perihematomal edema 24 and 72 hours after ICH (P<0.05). Inflammatory response occurred in and around the blood clot after ICH. characterized by the infiltration of neutrophils and macrophages. Five sessions of preconditioning with HBO reduced perihematomal inflammatory response 24 hours after ICH (P<0.05).Conclusions The present study demonstrates some sessions of preconditioning with HBO can attenuate brain edema after ICH. and inflammation may be the mechanism of brain injury after intracerebral hemorrhage.