The Effect Of Glucocorticoid On The Airway Injury Induced By Chlorine

Objectives: To observe the injuries of the upper and lower airway in rats after inhaling chlorine of different concentrations.To evaluate the effects of glucocorticoid of different doses on the larynx and lung in rats after injury.Methods: Rats were placed in chlorine container with different concentrations(50ppm,150 ppm,and 250ppm)for 15 minutes.We observed the inflammatory and pathology in the larynx,the arterial blood gas,inflammatory cell in bronchoalveolar lavage fluid,and the wet/dry lung.We treated rat with dexamethasone of different concentrations(50 mg / kg,100 mg / kg body and 150 mg / kg)after withdrawal of chlorine immediately.We examined the above-mentioned indexes after 60 min.We especially examined the same indexes treated by dexamethasone of 100mg/kg after 60 min when the rat left the chlorine at 0min,5min,10 min.Results: There were significant differences in the extent and location of airway injury after the rats exposing to different concentrations of chlorine.With the increase of chlorine concentration,the upper and lower airway injury increased.The location of injury after inhalation of low concentrations of chlorine was mostly in the upper airway,while high concentrations of chlorine both in the upper and lower airway damage.With appropriate dose of glucocorticoid(dexamethasone)in the early stage,the damage of the larynx and lungs of the rats was alleviated and delayed in different degrees.Conclusion: Early administration of appropriate dose of glucocorticoid can effectively relieve laryngeal and lung injury caused by chlorine inhalation.