A Morphologic Study of Long-term Retention of Fluorocarbon After Liquid Ventilation

To determine how long perfluorinatedhydrocarbons remain in the lung after they are used for lungventilation in dogs, and to determine if residual perfluorinatedhydrocarbons cause structural alteration or an inflammatory reaction ofthe lung. Adult dogs were anesthetized andreceived ventilation with oxygenated perfluorinated hydrocarbon liquid.Morphologic studies of tissue from the lungs of these dogs wereperformed at intervals of a few minutes to 10 years after reconversionto breathing gas. University College ofMedicine. Adult mongrel and beagledogs. Anesthetized adult dogs breathedoxygenated liquid fluorocarbons for 1 h and then were reconvertedto breathing air. Three fluorocarbons, FX-80(C8F16O; 3M Company; St. Paul, MN), Caroxin-D(C10F22O2; P-1D; Allied ChemicalCompany; Morristown, NJ), and Caroxin-F(C9F20O; P-12F; Allied Chemical Company), wereused. Morphologic studies of the lungs of these animals were performedimmediately after restoration of air breathing and at intervals for upto 10 years. Not all animals were studied at each time interval. A transient, acute inflammatoryreaction was followed by a massive influx of macrophages, which were atfirst intra-alveolar and later interstitial, especially around vesselsand bronchioles. Fluorocarbons remained in the lung in diminishingamounts for at least 5 years, as evidenced by persistent vacuolatedmacrophages in the alveoli, interstitium, and hilar lymph nodes;fluorocarbon was also detected in these tissues by chemical assays. Inno case was there fibrosis or any other structural alterationassociated with the residual fluorocarbon, which suggests that it wasinert. At 10 years, no evidence of residual fluorocarbon was seenmorphologically.