Effect of inhalation of salbutamol, beclomethasone dipropionate & ipratropium bromide on mucociliary clearance in some patients with chronic stable bronchial asthma.

BACKGROUND & OBJECTIVES: Asthma is now regarded as an inflammatory disease and bronchial inflammation may disrupt mucociliary function. Inhaled drugs may act by improving mucociliary function. The aim of the study was to investigate the effect of salbutamol, ipratropium bromide and beclomethasone on mucociliary clearance in patients with chronic stable asthma and to compare the efficacy of these drugs on mucociliary clearance.

METHODS

Ten patients with chronic stable asthma were enrolled in the study, but two patients did not complete the study. Patients with bronchial asthma were chosen on clinical grounds. (99m)Tc phytate radioaerosol generated through a nebulizer, was given to each patient on four days. After each administration the radioactivity over the thorax was constantly measured in sequential frame mode for 120 min. Radioactivity in the thorax was also measured after 24 h. A base-line pulmonary function test with reversibility was obtained. Salbutamol, ipratropium bromide, beclomethasone dipropionate and placebo inhalation were given randomly to each patient on four days.

RESULTS

The mean age of patients (n = 8) was 36 +/- 9.3 yr and mean duration of symptoms was 5 +/- 6.6 yr. There was no visual impression that mucociliary clearance was enhanced with any of the drugs. The time activity curves did not show any visually recognisable change in slope. In only one patient the curve tended to show a steeper slope with ipratropium inhalation. In the rest of the patients the curves showed no difference at all with medication when compared with placebo. All the quantitative indices analyzed by two-way ANOVA at the end of one and two hours were comparable for the three test drugs and placebo. None of the three test drugs demonstrated statistically significant mucociliary clearance effect compared with placebo. However, the temporal difference in airways clearance efficiency (ACE) was significant with beclomethasone and ipratropium bromide.

INTERPRETATION & CONCLUSION: Inhalation of any of the three drugs tested did not produce any immediate improvement in mucociliary clearance as compared to placebo in patients with stable bronchial asthma suggesting the need for further studies using higher doses of drugs for longer duration in a large sample.