Materials and Methods
This study was a retrospective cohort study performed at a tertiary children’s hospital in the Southeastern US with annual ED visits of 74,000 before the pandemic. All emergency department visits for patients under 24 months of age from March 2017 through February 2022 with an ICD-10 diagnosis code for bronchiolitis (J.21) coded at any time during their hospital stay. There were no exclusion criteria. Demographic information including age, gender, race and ethnicity were collected form the medical record. Visit information including acuity (based on triage Emergency Severity Index level), disposition (admitted, discharged, expired), admission unit, use of high flow nasal cannula, albuterol, and chest radiographs during ED visit or after admission, along with viral respiratory testing results were extracted. Viral respiratory testing from nasopharyngeal swabs included three possible panels that could be ordered at the prescriber’s discretion including a viral respiratory panel (VRP) polymerase chain reaction that tested for 15 common viruses as well as Sars-CoV-2, RSV, and influenza antigen detection, and a rapid BioFire® FilmArray® respiratory panel. Human rhinovirus is not distinguished from other enteroviruses on these tests and is reported as “rhino/enterovirus.” Data from the three years prior to the pandemic (2017, 2018, 2019) were compared with “pandemic years” 2020 and 2021. A year was a 12 month period from March to February to help align with the emergence of COVID within the United States in March of 2020.
Basic database management and analysis of descriptive statistics were performed using Excel and SSPS statistical software. Comparisons of differences among and within the 5 year study samples were accomplished using the One Way ANOVA with post hoc pairwise multiple year comparisons using Tukey’s HSD at alpha =0.05. For nonparametric group analyses, Kruskal-Wallis ANOVA with the post hoc multiple group Bonferroni correction with an alpha of 0.005 was used. Year to year comparisons of the proportions of use of therapies, medications, orders or unit specific admissions was performed using a 95% confidence interval estimation of the differences of proportions (no continuity correction). Intervals of the difference in proportions not inclusive of 0 were considered statistically significant at p<0.05. This study was approved by the University of Alabama at Birmingham Institutional Review Board under exempt category four, protocol number IRB-300006644-004. The datasets generated during and/or analyzed during the current study are not publicly available, but are available from the corresponding author on reasonable request.