title: Tracheobronchial cytologic changes during prolonged cannulation.
abstract: The tracheobronchial cytology of eighteen patients undergoing prolonged mechanical ventilation were examined for the type of cell population present, together with the morphologic integrity of the ciliated epithelial cells 1, 3, 5,10, and 20 days after tracheal cannulation. Smears obtained from patients recovering from cardiac surgery were different from all others in that: (1) they contained fewer epithelial cells (ciliated and squamous) which disappeared earlier; (2) they initially had more pus cells which appeared earlier; (3) they originally contained more histocytes but these were not found after the 5th day after cannulation; and (4) their ciliated epithelial cells displayed more cytomorphologic changes. Differences in cytology were attributed to impaired cardiac output in these patients. The reduced perfusion pressure of the vasculature of their tracheobronchial tree was presumably unable to sustain the lateral wall pressure of tube cuffs pressure, which further impaired tracheal perfusion. Less reparative processes (squamous metaplasia and early appearance of histiocytes) were also found in patients following cardiac surgery, together with early invasion of smears by pus cells indicating premature lowered resistance to bacterial infection.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001980:Bronchi / Q000473:pathology*; D006348:Cardiac Surgical Procedures; D002648:Child; D002923:Cilia / Q000473:pathology; D006331:Heart Diseases / Q000473:pathology; D006644:Histiocytes / Q000473:pathology; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D008875:Middle Aged; D012121:Respiration, Artificial / Q000009:adverse effects; D013492:Suppuration / Q000473:pathology; D013997:Time Factors; D014132:Trachea / Q000473:pathology*