Tracheobronchial hemorrhage

Immediate effects included dyspnea, coughing, irritation of the eyes and throat, headache, giddiness, chest pain, abdominal discomfort. Subjects also exhibited hilar congestion, bronchial vasculature markings, respiratory incapacitation, tracheobronchial congestion, chronic bronchitis, scattered hemorrhages, bronchial erosion. Bronchial smears taken from 28 subjects 5 d after exposure showed basal-cell and goblet-cell hyperplasia, acute inflammation, and chromatolysis... 

All subjects exhibited dyspnea, cough, bronchospasm. Other effects included irritation of the eyes and throat, headache, abdominal pain, vomiting, giddiness. 5 subjects had cyanosis, X rays showed cases of patchy infiltrates, hilar congestion. Pulmonary function was affected in most subjects bronchoscopy revealed tracheobronchial mucosal irritation. Some subjects had hemorrhagic spots, erosions, ulcers. In a follow-up of 16 patients for 1 yr, 4 reported... 

Acute, heavy exposure to SM causes loss of the columnar cells of the upper respiratory tract, peribronchial edema, hyperemia of the blood vessels, cellular infiltrations in the submucosa, and intense vacuolization and disorganization of the cytoplasmic and nuclear structures (Emad and Rezaian, 1997, 1999). Pulmonary hemorrhage, pulmonary edema, and respiratory failure similar to ARDS may also occur. These cytotoxic effects are associated with acute thermal injury sustained by the airway mucosa and lead to scarring and development of stenosis of the tracheobronchial tree as was observed in 9.64% of the SM-exposed patients. 

Rarer complications of plastic tube stents include tracheobronchial ulceration with secondary hemorrhage, perforation of the tracheobronchial wall with secondary mediastinitis and septic shock, tumor overgrowth at the proximal or distal stent margin. 

Self-expanding metalhc stents create constant pressure on the tracheobronchial wall. This might lead to wall perforation, hemorrhage, mediastinitis and even erosion of adjacent vascular structures. 

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