[Microcirculation and oxygen tension in the cerebral cortex of rats with hemorrhagic shock]

Microcirculatory disturbances in pia mater are followed by change in oxygen tension in the brain cortex. Immediately after bleeding initial decrease of oxygen tension by 60-70% of the basal level was observed. This decrease was induced by initial vasoconstriction and brain cortex hypoxia. After compensation of blood circulation supervened and the cortical blood flow was set to a lower level (30-40 minutes after the decrease), there occurred a phase of oxygen level stabilization. The oxygen tension remained unchanged for a long time and decreased very slowly. More rapid fall of oxygen tension was noticed only at the end of the fourth hour when circulation decompensation set in.