ADVERSE EFFECTS OF INHALATION OF EXCESSIVE AMOUNTS OF NEBULIZED ISOPROTERENOL IN STATUS ASTHMATICUS

The inhalation of excessive amounts of nebulized isoproterenol and related compounds may produce adverse effects in status asthmaticus. Nine of 17 patients, whose deaths were caused primarily by asthma, used these preparations excessively and apparently more and more to accomplish less and less. Three entered into a locked-lung syndrome when prolonged inpatient treatment with corticosteroids and all other usually employed modalities failed to produce relief of wheezing, which persisted, increased, became refractory to very large doses of isoproterenol given by hand nebulizer and intermittent positive pressure breathing apparatus, and ultimately caused death. Thirty living patients, with severe asthma resistant to all usual forms of treatment, including corticosteroids, improved when they stopped overusing nebulized isoproterenol compounds. One of these showed no bronchodilating response after recovery. One normal person had evidence of irritation of the upper and lower respiratory tract after inhalation of excessive aerosol from the Isuprel Mistometer but no evidence of bronchial obstruction. These data are consistent with the hypothesis that therapeutic doses of these preparations are well tolerated and effective against bronchial obstruction due to asthma, but overusage may induce and/or maintain irritation of the air passages and intractable asthma. © 1969 The C. V. Mosby Company.