Practice in bronchiolitis management in Polish hospitals-a multicenter retrospective cohort study

Bronchiolitis is one of the main reasons for the hospitalization of young children. Based on updated recommendations, only supportive therapy is recommended for treatment. In Poland, many children that are hospitalized with bronchiolitis undergo a treatment that is not supported by current research. The study aimed to assess clinicians' adherence to the guidelines. This was a multicenter retrospective study of hospitalized infants with bronchiolitis; a cohort study design was utilized. Data were collected in four Pediatric Departments in Poland. All infants aged less than 24 months that had been hospitalized for their first and subsequent episodes of acute bronchiolitis from January 1, 2021, to December 31, 2022, were included. The exclusion criterion was an age over 24 months. A total of 629 infants with a median age of 8.5 months were included in this study. The medical interventions and treatments varied between the four hospitals. Laboratory blood tests were run for almost all children (99.5%), and the percentage of children for which a chest X-ray was performed ranged from 1.3% to 44%. The other measures were the use of intravenous hydration (51.3%-93.3%), use of hypertonic saline nebulization (1.3%-43.6%), use of normal saline nebulization (10%-95.1%), use of oxygen (7.3%-42%), use of beta-mimetics (19.1%-89.4%), use of nebulized steroids (8%-76.9%), use of systemic steroids (0.9%-42%), use of nebulized adrenaline (0%-8.1%), and use of antibiotics (12%-21.8%).

In total, 70% of infants who were hospitalized in four hospitals in Poland underwent examinations and treatment methods that are not supported by current guidelines and evidence-based research. This study shows that non-recommended medications are overused in bronchiolitis treatment, and there is a need to take action to implement the guidelines into healthcare providers' work.

• Bronchiolitis is a lower respiratory tract viral infection and is one of the main reasons for hospitalization among young children. • Only supportive therapy is recommended in the guidelines. • Bronchodilators, nebulized adrenaline, nebulized or systemic steroids, and antibiotics are not recommended.

• Non-recommended medications are overused in bronchiolitis treatment in Poland. • Up to 70% of hospitalized children in the studied centers underwent treatment that is not supported by guidelines.