To summarize the experience in diagnosis and treatment of sudden collective chlorine poisoning and discuss the characteristics of the disease and effective coping strategies.

To retrospectively analyze the cases of collective chlorine gas poisoning caused by four sudden chemical plant chlorine leakage accidents, which were organized and participated in the rescue by the authors from June 2009 to May 2017. A total of 1 539 patients, of which 746 were males and 793 women, aged from 7 d to 90 years old, mean age (43.8±0.69) years old. The patients were diagnosed and classified according to the symptoms, signs, imaging examinations (chestX-ray and CT) and laboratory results of arterial blood gas analysis and other tests. For patients with severe acute pulmonary edema, on the basis of comprehensive treatment, an innovative therapy of 20AA combined amino acid combined with vitamin B₆ and short-range anisodamine combined with dexamethasone shock therapy was used. As soon as the condition is stable, the traditional Chinese medicine "Chaihuangshenquduguben" was put to use for an auxiliary conditioning treatment. the characteristics of clinical manifestations, chest X-ray and chest CT, laboratory examinations (blood routine, blood biochemistry, and arterial blood gas analysis) during the early phase of poisoning and disease progression in critically ill patientswere observed and summarized.Successrate of rescue wascalculated and the effectiveness of the above-mentioned innovative treatment methods for patients with acute chlorine poisoningwas evaluated.

Among the 1 539 acute chlorine poisoning patients, 1 041 (67.6%) had mild irritative reactions, 394 (25.6%) were mildly poisoned, and 79 (5.1%) were poisoned, a total of 25 cases (1.6%) severe poisoning. The progression of acute pulmonary edema in patients with severe chlorine poisoning is divided into stimulation phase, latency phase, episodes of pulmonary edema and recovery phase. There are obvious differences in symptoms, signs, and auxiliary examination results in each phase, but after a latency period of 1 to 48 h, in the above treatment, the symptoms generally began to improve within 96 hours and gradually entered the recovery period. After 2 weeks of continuous treatment, the symptoms can basically heal. 1 539 patients were cured and none died. in the follow-up observation of 25 patients with severe acute chemical pulmonary edema, no long-term effects such as pulmonary fibrosis and tumorigenesis were found.

The development of chlorine poisoning disease is rapid, the prevention and treatment of pulmonary edema is the key to treatment. On the basis of comprehensive treatment, the use of 20AA compound amino acid combined with vitamin B₆, short-term anisodamine combined with dexamethasone impact therapy and Chinese traditional medicine prescription "Chai Huang ShenQu Du Gu Ben" has a good effect on it.