Time of onset of pathological findings of pulmonary oxygen toxicity (POT) in primates and humans
| Day | POT phase | Primates | Day | POT phase | Humans |
| 1 | 1 | Tracheobroncholitis, mucous flow decreased | |||
| 2 | Exudation | Alveolar oedema, septal wall oedema, distention lymphatic vessels, decrement alveolar type 1 cells | 2–5 | Exudation | Denuded alveolar type 1 cells, oedematous endothelial capillary cell swelling, necrosis respiratory epithelium, squamous metaplasia tracheal and bronchial mucosa, deposition eosinophilic slough, alveolar and interstitial oedema, formation hyaline membrane, cilial loss, decreased mucociliary transport |
| 4 | Resolution, formation hyaline membrane, influx inflammatory cells | ||||
| 5 | Proliferation | Increment alveolar type 2 cells, fibroblast infiltration | 5–88 | Proliferation | Proliferation of alveolar type 2 replacing alveolar type 1 cells, derangement of collagen and elastin, incorporation of hyaline membranes into the septal walls, fibroblastic proliferation, collagen fibre deposition, fibro-proliferative organisation of intra-alveolar exudate, infiltration with inflammatory cells, interstitial lung fibrosis, emphysematous alveoli with areas of fibrosis, cilial loss |
| 8 | Intra-alveolar hyaline membranes, thickening of the alveolar-capillary membrane, leukocytic infiltration, marked cellular proliferation of abnormal alveolar type 2 cells, haemorrhagic areas, accumulation of intracellular water | ||||
| 12 | Extravascular lung water within the pulmonary parenchyma and interstitial space, invasion of fibroblasts and macrophages | ||||
| 56 | Air-blood barrier thickened, increase in collagen content, intra-alveolar septal scarring, alveolar air volume diminished |