The present study was intended to examine the oxygen toxicity to respiratory tract and lung after exposure to 3-atmosphere absolute (3 AT.A.) of hyperbaric oxygenation condition for 3 hours. Laboratory animals were rabbit, rat and chicken. Fifteen of each animals were exposured to 3 AT.A. of hyperbaric condition for 3 hours, and others were used as control groups. Onset of convulsion, blood analysis, lung weight per body weight ratio, and hstopathological observation of respiratory tract and lung parenchyma were performed.
The results were as follows:
1. The rat group showed higher degree of tolerance as compared with other laboratory animal groups represented by delayed onset of convulsion.
2. The average value of red blood cell, hemoglobin and hematocrit was tend to be decreased after exposure to the rapid hyperbaric oxygen condition in all experimental groups.
3. As a quantitative measurement of oxygen toxicity to lung, lung weight per body weight ratio was significantly high in rat, rabbit and chicken in order.
4. Histopathological changes in respiratory tract were loss of cilia and epithelial damage, such changes were more severe in the upper part and less or no damage in the lower part.
5. Histopathological alterations of the lung parenchyma by oxygen toxicity included vascular congestion, pulmonary´ edema, hemorrhage and emphysema.
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