Mitchell L. Rhodes

Foreign body removal: a new role for the fiberoptic bronchoscope.

Artificial and animal lung models initially were used to investigate the removal of foreign bodies from the tracheobronchial tree with the flexible fiberoptic bronchoscope. Different extraction instruments (claw, basket, forceps, and balloon catheter) were passed separately through the channel of the bronchofiberscope, and tested for usefulness prior to human application. The Fogarty balloon catheter served as a valuable aid in dislodging impacted objects so that the operator could then grasp them with the claw, basket or forceps. The wire claw recovered many of the metallic and organic objects, the wire basket was successful in retrieving only the bulky objects and the forceps (ACMI) was effective in capturing all of the metallic foreign bodies. These techniques, developed in our laboratory, are now being used to augment rigid bronchoscopy in the removal of foreign bodies from adults and older children. At the present time fiberoptic foreign body removal is not recommended for pediatric cases because of the small diameter of the trachea and glottis in infants and young children.

Selective bronchial catheterization for the study of experimental lung damage in the rabbit.

Summary A nonsurgical rabbit model is described for study of selected lung segments. The technique is easily learned and does not require unusual dexterity. The method utilizes intrabronchial catheterization through a plastic endotracheal tube. The remainder of the lung may serve then as a control.

Light and immunofluorescent study of the Arthus reaction in the rabbit lung

A localized Arthus reaction was produced in the lung of sensitized rabbits by delivery of antigen into a lower lobe bronchus using a method of selective bronchial catheterization under fluoroscopy. The rabbits were sensitized with bovine immunoglobulin G (B-IgG) in incomplete Freunds adjuvant (IFA) to produce precipitating antibody without classic delayed hypersensitivity. Pulmonary histopathology was studied at intervals following antigen challenge, using light and immunofluorescent microscopy. Gross lesions peripheral to the lower lobe bronchus receiving antigen were found within 12 hr. Subsequent necrosis resulted in a dense scar by 6 wk. Microscopically, early lesions were typified by localized bronchitis, bronchiolitis, alveolitis, and vasculitis with exuberant exudates containing predominantly polymorphonuclear leukocytes. Extensive focal necrosis was present by 72 hr. Immunofluorescent studies revealed the presence of B-IgG, rabbit IgG, and complement (C3) in and around bronchi, bronchioles, alveoli, and vessels. No granulomatous lesions were found, and proliferation of alveolar lining cells was not detected in these studies. Thus, the lung can participate in an acute Arthus reaction following local antigen challenge in systemically sensitized animals. The pathology more closely resembles a necrotizing bacterial pneumonia than an interstitial or hypersensitivity pneumonitis under the conditions of this experimental system. Implications for human disease are speculative.

Ultrastructural studies of acute hypersensitivity pneumonitis in rabbits

Abstract Acute experimental hypersensitivity pneumonitis in rabbits was studied using scanning and transmission electron microscopy. Scanning electron microscopy reveals the three-dimensional architecture of lesion localization, alveolar cellular filling, and scptal thickening, which typify this animal model. Transmission electron microscopy has identified the macrophage as the dominant cell filling alveolar spaces with variable numbers of lymphocytes and granulocytes. Septal thickening is also accompanied by increased cellularity involving septal cells and fewer numbers of other mononuclear and polymorphonuclear cells. No evidence of proliferating alveolar lining cells was found.