Impact of constant and breath-synchronized nebulization on inhaled mass of nebulized budesonide in infants and children

Pediatr Pulmonol. 1999 Sep;28(3):187-93. doi: 10.1002/(sici)1099-0496(199909)28:3<187::aid-ppul5>;2-j.


The aim of the present study was to compare the output of a breath-synchronized jet nebulizer to a conventional constant output nebulizer over a fixed period of time in terms of inhaled mass of budesonide, i.e., the amount of budesonide deposited on a filter interposed between the nebulizer and the face mask. One hundred and sixty-five asthmatic children (103 boys) were enrolled in this open, randomized, crossover trial. Their age ranged from 6 months to 7.9 years, height from 69 to 132 cm, and weight from 8.2 to 31.3 kg. Their duration of asthma ranged from less than 1 to 7 years. Budesonide suspension, 0.5 mg mL-1, 2 mL, was used. With 5 min of constant output nebulization, the mean inhaled mass of budesonide in percent of the nominal dose was 11.4% in the youngest children and 14.9% in the 7-year-old children. Expressed in percent of the total output of budesonide, i.e., the amount that left the nebulizer as an aerosol, the inhaled mass ranged from 34.6-48.6%. Thus, 51.4-65.4% of the total output was deposited on the expiratory filter. With 5 min of breath-synchronized nebulization, the mean inhaled mass ranged from 10.5-14.9% of the nominal dose. For the youngest patients less than 3-4 years of age, it was approximately 80-90% of the total output. For the older patients the inhaled mass was approximately 95% of the total output, i.e., only small amounts of budesonide were deposited on the expiratory filter. For both modes of nebulization the between-subject variation in inhaled mass was large: up to 6-fold in the young children and 3-4-fold in the older ones. The results of the present study showed that the inhaled mass of budesonide was significantly age-dependent with both modes of nebulization, i.e., the inhaled mass was less in younger children. Breath-synchronized nebulization resulted in reduced waste of drug during expiration.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Age Factors
  • Asthma / drug therapy*
  • Bronchodilator Agents / administration & dosage*
  • Budesonide / administration & dosage*
  • Child
  • Child, Preschool
  • Cross-Over Studies
  • Equipment Design
  • Female
  • Filtration / instrumentation
  • Humans
  • Infant
  • Male
  • Nebulizers and Vaporizers*
  • Respiration
  • Tidal Volume


  • Bronchodilator Agents
  • Budesonide