2.1-Study design, participants, and definitions
From March 2017 through March 2020, we conducted a prospective, randomized, controlled study comparing the effect of HFNCO and LFO therapy on children diagnosed with bronchiolitis and requiring oxygen supplementation in Ege University Medical Faculty Children Hospital. The trial performed followed the recommendations of the Consolidated Standards of Reporting Trials statement of 2010.18
Participants eligible for the study were children aged between 1-24 months with clinical-diagnosed moderate to severe bronchiolitis, hypoxia, and admission to the general pediatric ward. Exclusion criteria included admission to ICU for MV, receiving LFO or HFNCO therapy at other facilities before arrival, an underlying medical condition (e.g., congenital heart disease, chronic lung disease, neuromuscular disease, metabolic disease, or immunodeficiency), a craniofacial malformation, upper airway obstruction, pneumothorax, or nasal trauma. Bronchiolitis was diagnosed based on the 2014 AAP Clinical Practice Guideline.17 The severity of the disease was considered using CRS involving RR, retraction, dyspnea/consciousness status, and wheezing (Supplemental Table 1; p1-2).19Each parameter in CRS ranges from 0 to 3 points. The higher total score is the worst presentation clinically. Participants with CRS between 5 and 8 points are considered moderate bronchiolitis, and those with CRS between 9 and 12 points are defined as severe bronchiolitis. Hypoxia was defined as peripheral capillary oxygen saturation (SpO2) <92% while breathing room air.17