Wheezing in Infants: The Response to Epinephrine

There is significant controversy about the role of bronchodilator therapy for wheezing in infants. A double-blind, randomized trial of subcutaneous epinephrine v normal saline was conducted in children <24 months of age evaluated at Yale-New Haven Hospital. Respiratory assessments using a newly developed Respiratory Distress Assessment Instrument were made at baseline and 15 minutes after each of two injections. Relief of respiratory distress was assessed using strict a priori criteria based on changes in respiratory rate, wheezing, and retractions as scored in the Respiratory Distress Assessment Instrument. Significantly more children improved their respiratory status with epinephrine (nine of 16) than placebo (one of 14) (Fisher exact test, P = .0067). Paired data in individuals receiving placebo and then epinephrine confirmed this (Wilcoxon signed ranks test, P < .01). Sixty-three percent of patients <12 months and 92% of those 12 to 24 months improved with epinephrine, as did seven of ten children with respiratory syncytial virus bronchiolitis. In many children, response to the initial epinephrine injection was not indicative of final response. Results of this study demonstrate the effectiveness of epinephrine in the treatment of acute wheezing in children <24 months of age.