Clinical and morphologic studies were carried out in 230 patients suffering a grave course of an exacerbation of infectious bronchial asthma. A protracted attack of the condition was detected in 70 patients, in 80 patients status asthmaticus, Stages I-II was found, 50 patients suffered a Stage III status asthmaticus, and 30 patients were hospitalized in the terminal state and died within 12 hours since admission. The circulatory, metabolic, immunologic homeostasis parameters were studied, morphologic, examination of pulmonary, tracheal, cardiac, cerebral, splenic and hepatic tissue was carried out in 30 patients who died at the height of the status asthmaticus. The authors have analyzed the contribution of the homeostasis parameters to the formation of the critical state in status asthmaticus and the relationships of these parameters between each other and with the condition severity. The severity of the patients' condition was found closely related to the degree of respiratory, circulatory, and metabolic disturbances. Respiratory failure and circulatory disorders were the principal clinical manifestations of status asthmaticus, though the disorders of the metabolic and immunologic homeostasis also much contributed to the formation of a critical condition due to status asthmaticus. Characteristic histomorphologic changes of the viscera, detected at autopsy, were the morphologic equivalent of these clinical symptoms. The findings regarding status asthmaticus as a critical state that is characterized by the development of multiorgan insufficiency involving the formation of incompetence of natural detoxication routes.