(338) Nebulized N-Acetylcysteine for Acute Bronchiolitis in Inpatient Hospital Use: Pilot Study

Introduction: Acute bronchiolitis was responsible for approximately 108,000 hospitalizations and an estimated cost of $734 million in the United States in 2016. It is associated with cellular swelling and excessive mucous production due to the proliferation of goblet cells leading to airway obstruction, hyperinflation, increased airway resistance, atelectasis, and increased ventilation-perfusion mismatch. Currently, the American Academy of Pediatrics guideline recommends only supportive care for acute bronchiolitis. N-Acetyl Cysteine (NAC) is an antioxidant, anti-mucus compound that increases intracellular glutathione and cleaves disulfide bonds, resulting in the breakdown of mucoproteins in lung mucus, thereby thinning mucous secretions. The purpose of this study is to evaluate the effectiveness of nebulized NAC in the treatment of acute bronchiolitis.

Methods: We performed a double-blinded randomized controlled pilot study that included children less than two years of age admitted to our PICU with a diagnosis of acute bronchiolitis to determine if nebulized NAC improves patient symptoms, reduces the duration of non-invasive ventilation, and decreases hospital stay compared to standard supportive care. Eligible patients were randomized into 2 groups (NAC or non-NAC (control)). Patients in both groups were scored every 12 hours before and after their assigned treatment. 2mL nebulized 10% NAC solution was used in the NAC group.

Results: Twenty patients met eligibility criteria for analysis with ten belonging to the NAC group and 10 belonging to the control group. Pre-treatment bronchiolitis scores between NAC and non-NAC groups were insignificant (P=0.161); however, post-treatment bronchiolitis scores were lower after the use of nebulized NAC compared to those that only received supportive care (P=0.068). No significant difference was noted in the length of hospital stay or duration of non-invasive ventilation (P=0.702 and P=0.765, respectively). No adverse events with nebulized NAC were reported.

Conclusions: The pilot study provided useful information about the utility and safety of nebulized NAC as a treatment for acute bronchiolitis. A larger sample size will be required to better assess other variables analyzed in this study.