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Acute laryngeal and bronchial obstruction after CS (o-chlorobenzylidenemalononitrile) gas inhalation


CS gas (o-chlorobenzylidenemalononitrile) is one of the most commonly used riot agents. It can create excessive tearing, conjunctivitis, uncontrolled blinking (blepharospasm) and a sensation of burning and pain at initial exposure. Pulmonary edema (ARDS) and/or diffuse airway lesions on human would be lethal after CS inhalation. We report a case with acute laryngeal and bronchial obstruction due to vocal cord edema and extensive crusting at glottic level, trachea and bronchi. The CS gas was sprayed in a 6 × 6 m2 closed room, and she was exposed to increased concentration of the gas for 10 s. Surprisingly, her initial symptoms were raised 21 days after CS spray exposure.

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Correspondence to C. Duman.

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Karaman, E., Erturan, S., Duman, C. et al. Acute laryngeal and bronchial obstruction after CS (o-chlorobenzylidenemalononitrile) gas inhalation. Eur Arch Otorhinolaryngol 266, 301–304 (2009).

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  • CS gas (o-chlorobenzylidenemalononitrile)
  • Laryngeal obstruction
  • Bronchial obstruction