Respiratory effects of normobaric oxygen toxicity in awake guinea-pig.

We studied the time course of the respiratory events in awake guinea-pigs catheterized with a chronic arterial cannula, exposed to 100% O2 during 48 hr and after air return breathing. 2. The oxygen toxicity has a pulmonary and respiratory expression: clinical, histological and biochemical data show that death is related to the asphyxia generated by acute pulmonary edema. 3. The O2 toxicity respiratory effects show striking differences in rats and guinea-pigs; the differences belong to a specific and particular lymphatic system in the rat. 4. Rat and guinea pig offer two different models of pulmonary edema, (the first is characterized by absence of arterial hypoxemia) and in consequence two different models of lung oxygen toxicity.