We investigated the efficacy and the side effects of "high-dose
isoproterenol continuous nebulization" for childhood
status asthmaticus. Subjects were 34 children who were hospitalized and underwent the nebulization
therapy. The 50 ml
solution of 0.5% dl-
isoproterenol was diluted in 500 ml of
normal saline and nebulized through an ultrasound
nebulizer. The period of continuous nebulization was 25.5 +/- 16.0 hours. The Wood's clinical score clearly decreased in 32 cases, the average score changing from 7.7 +/- 0.8 to 2.9 +/- 1.3. Heart rate was elevated significantly during the first 3 hours (156 +/- 25/min at the start of the nebulization, 180 +/- 20/min at 1 hour, 171 +/- 23 at 3 hours), and then it decreased gradually to 122 +/- 25/min at the cessation of the nebulization. Serum GOT, LDH, CPK, and
potassium were elevated after the nebulization compared with the values before the treatment, though the changes were not statistically significant. CPK-MB fraction after the nebulization was higher than normal range in 12 of 13 subjects. Of 34 subjects, 11 (32%) complained
nausea or vomited, 2 showed
arrhythmia on ECG (ventricular premature conduction), 1 developed myocardiac
infarction, and 1 developed possible
heart failure, some of which might be attributable to the pharmacological side effects of
isoproterenol nebulization. We conclude that "high-dose
isoproterenol continuous nebulization" is an effective method for childhood
status asthmaticus, but there is some risk of serious side effects. This method was originally developed as a method indicated for the case of
respiratory failure or threatened
respiratory failure following
status asthmaticus, and we should not extend the indication of this method thoughness.