Experience with inhaled surfactant in the treatment of severe bronchial asthma exacerbation

Introduction. Bronchial obstruction in asthma, resulting from the contraction of smooth muscle, swelling of the mucous membrane, and hypersecretion of bronchial mucus, may also be partially attributed to impaired lung surfactant function.

Aim. To evaluate the efficacy of inhaled surfactant therapy in patients with severe bronchial asthma (SBA) exacerbation and to identify factors associated with treatment response.
Materials and methods. The study included 42 hospitalized patients aged ≥ 18 years with severe bronchial asthma exacerbation (IV–V), who were divided into study and control groups depending on the treatment received. In addition to standard management of asthma exacerbation, the study group received inhaled surfactant at a dose of 75 mg via nebulizer twice daily for 5 days. Patients were followed up at two stages: during hospitalization for 7 days after randomization, and 6 months after completion of the treatment course.

Results. At baseline, the groups were comparable in most parameters, except that asthma control assessed by the ACQ-5 questionnaire was lower in the main group (2.9 vs. 2.1; p = 0.001). During inhaled surfactant therapy, a significant reduction in ACQ-5 score was observed as early as 3 days, with a further decrease to 1.5 points by day 7, and this level was maintained at 6 months (in the control group at 6 months – 2.4 points; p < 0.001). The need for rescue medication in the main group decreased from 3.6 to 0.6 times per day by day 7 (in the control group – from 3.0 to 2.1 times per day, respectively; p < 0.001). Spirometry parameters (FEV1, MEF25–75%) significantly improved in the surfactant group at day 7, and FEV₁ remained improved at 6 months, whereas in the control group FEV₁ decreased at 6 months. Also 6 months after inhaled surfactant therapy the “group × time” interaction was statistically significant for ACQ-5, rescue medication use, and most lung function parameters (p < 0.05), indicating the superiority of surfactant therapy. Blood leukocyte and eosinophil levels showed no significant intergroup differences. Factors associated with the effectiveness of surfactant therapy were baseline MEF_25% (OR = 0.963; p = 0.048), baseline MEF_50% (OR = 0.948; p = 0.040), and baseline blood leukocyte count (OR = 0.446; p = 0.021). The number of exacerbations over 6 months was significantly lower in the surfactant group, with a median of 0.0 (0.0–1.0), compared with 1.0 (1.0–1.0) in the control group (p = 0.003).

Conclusions. Inhaled surfactant therapy in patients with severe bronchial asthma exacerbation leads to a statistically significant improvement in asthma control, reduction in rescue medication use, positive changes in lung function parameters, and a decrease in the frequency of exacerbations within 6 months after treatment. The highest chance of treatment effectiveness is observed in patients with lower baseline MEF_25%, MEF_50% and lower blood leukocyte count.

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