Reactive airway disease after chlorine gas exposure.

We read with great interest in the September 1991 issue of Chest the case report by Moore and Sherman.’ Chlorine gas exposure has multiple toxic effects on the respiratory system, including immediate airflow obstruction, ARDS, and death. The long-term effects can include abnormalities in gas transfer, restriction, and airflow obstruction. These generally resolve with time to a variable degree. Additionally, the severity and resolution of these effects appear to be related to the degree of exposure, premorbid pulmonary status, and the degree of hypoxemia on initial presentation. In 1990, we reported two cases of reactive airway dysfunction syndrome (RADS) following chlorine exposure to chlorine gas.5 Both patients had an asthmatic diathesis extending over time. One individual has had persistent asthmatic symptoms for the past six years; the symptoms have ameliorated with time, although she continues to be symptomatic. She is receiving minimal medication at the present time, compared with her immediate postexposure needs. Before exposure, she was neither a smoker nor an asthmatic. The other individual was also exposed to chlorine fumes. There was no history of preexposure asthma, and he had discontinued smoking several years prior to his exposure. Not only did this individual have asthmatic symptoms, which responded to bronchodilators, but he also had persistent hypoxemia, which has resolved over the years. His exercise stress test initially accentuated his hypoxemia, and his primary symptoms were those of dyspnea on exertion. His condition has ameliorated with time. Thus, chlorine exposure can present with asthmatic symptoms and BADS, as described by Brooks et al.’ Our experience has been that the amount of asthma (diagnosed either by symptoms or by the medication needs) ameliorates with time. Hypoxemia with poor cardiopulmonary reserve was observed in one individual, and this also resolved with time.