Bronchodilation test: Salbutamol or Ipratropium Bromide?

Abstract

Background: The evaluation of the response to bronchodilator in pulmonary obstructive pathologies is crucial for the diagnosis and clinical follow-up of the individuals. β-adrenergic agonists and anticholinergics are the most frequently used.

Objectives: To characterize the response of bronchodilation according to the drug used; to identify differences in response of bronchodilation according to the pathology; to determine the agreement of the response to bronchodilator considering Salbutamol (Sb) or Ipratropium Bromide (IB).

Methodology: Cross-sectional study. 141 individuals with airway obstruction were included (39 asthmatics and 102 COPD) and underwent two spirometry tests with an 8-day interval. In half of the sample Sb was used on the first visit and IB on the second, and in the other half the order was reversed. An increase of ≥12% and ≥200mL in FVC and/or FEV1 was considered a positive bronchodilation.

Results: The analysis of the means of study variables didn’t revealed significant differences (p>0.05) between Sb and IB. The average of the differences between the parameters was 60mL and 1.92% for FVC and 40mL and 1.53% for FEV1. Bronchodilation was positive in 17.7% of the sample (Sb), 19.1% (IB) and 26.2% (Sb+IB). In COPD group, a positive response was observed in 15.7% (Sb), 18.6% (IB) and 30.4% (Sb+IB) and in the asthma group 23.1% (Sb), 20.6% (IB) and 15.4% (Sb+IB). The Kappa agreement coefficient revealed that the response to bronchodilator is different depending of the used drug (Kappa=0.254; p=0.003).

Conclusion: The characterization of the response to the bronchodilator showed to be different according to the drug used, and it was found that asthmatic individuals respond mostly to Sb and COPD to the IB.