Intensive bronchial dilation test: A modified method for evaluating airway reversibility.

Background: A negative bronchial dilatation test (BDT) does not fully reflect the status of airway irreversibility in patients with severe obstructive or mixed ventilation dysfunction due to severe bronchospasm, mucus blockage, or insensitivity to bronchodilators, which will directly affect the subsequent diagnosis and treatment of those patients.

Objective: We retrospectively examined the feasibility of using the "intensive bronchial dilation test" (IBDT) for excluding false-negative BDT.

Methods: We retrospectively analyzed the clinical data of 82 patients with severe obstructive or mixed ventilation dysfunction in the Allergy department of Yantai Yuhuangding Hospital of Qingdao University. After the BDT, they all inhaled the triple atomized drugs (2 mg salbutamol, 1 mg budesonide, and 0.25 mg ipratropium) every 20 minutes in one hour and the lung function test was performed 15 minutes later, which was named as IBDT. All patients received another lung function test after 2 to 4 weeks of regular anti-inflammatory treatment. We compared the improvement of lung function indexes and the proportion of patients with reversible airway obstruction between BDT, IBDT, and 2 to 4 weeks of treatment groups.

Results: The lung function indexes were significantly improved after the IBDT than those after the BDT (all P values < 0.01) and the number of patients with reversible airway obstruction significantly increased from 31 to 61 after the IBDT (P < 0.001), but the proportion of patients with reversible airway obstruction after the IBDT did not differ from that of patients with reversible airway obstruction after 2 to 4 weeks of treatment. The accuracy and sensitivity of the IBDT in evaluating airway reversibility reached 91.46% and 89.71%, respectively, both of which were significantly higher than for the BDT (54.88% and 45.59%, respectively).

Conclusion: Our finding suggests that IBDT can more accurately and rapidly evaluate airway reversibility in patients with severe obstructive or mixed ventilation dysfunction when compared to BDT.