Cui X, Li Z, Teng Y, et al. - Researchers conducted this randomized, double-blind, crossover study to find out what pathophysiological changes in small airways are correlated with the use of a PM_2.5 removal device in children with asthma in their bedrooms. Participants in the study were 43 children (5-13 years old; 26 boys [60%]) with mild or moderate asthma. This investigation was carried out in a suburb of Shanghai, China, during a low-ozone season. Findings suggested a significant association of using a particle-removing device in bedrooms for 2 weeks with improved small airway mechanics, increased peak expiratory flow, and reduced pulmonary inflammation. Indoor air filtration has been associated with improved airflow in the small airways and decreased respiratory inflammation, making it an effective preventive step in the management of asthma.