Hyperbaric oxygen-induced seizure in a marine mammal, the seal.

KEREM, DAN,GERALD KOOYMAN,JOSEPH P. SCHROEDER,JAMES J. WRIGHT, AND CHARLES M. DRABEK. Hyperbaric oxygen-induced seizure in a marine mammal, the seal. Am. J. Physiol. 222(5) : 13221325. 1972.-A female yearling northern elephant seal, Mirounga angustirostris, and a female yearling harbor seal, Phoca vitulina were subjected to breathing oxygen at a pressure of 4.5 Ata in the restrained unanesthetized state inside a wet pressure chamber. The elephant seal showed first signs of central nervous system poisoning after 10 min of a 15-min compression period. A fullfledged convulsive seizure ensued shortly after decompression. The harbor seal was compressed for 20 min. The first apparent toxic symptoms occurred after 9 min. They increased gradually and were completely relieved by decompression. Recovery ot both animals was complete. Compared to other mammals these species seem especially vulnerable to acute oxygen toxicity, possibly on account of their breathing pattern.