Oxygen Tension of the Brain During Hyperoxic Convulsions

Abstract

The oxygen tension of the cerebral cortex of cats was determined by the use of the platinum cathode polarographic method. A descr. modification of existing techniques permits continuous recording in vivo without polarization or "poisoning" of the electrodes. Simultaneous increases in both the ambient atmosphere and the inspired O2 from 1 atm. (0 psi, gauge) to 6 atm. (75 psi, gauge) caused a rapid rise in cerebral O2 tension. This rise was between 10- and 50-fold. After the peak value was reached, a gradual decrease in cerebral O2 tension, approaching the initial level, was noted. Seizures occurred only when there was a rapid rise in cerebral O2 tension.