544 - Testing and Treatment Patterns in Infants ≤90 Days With Bronchiolitis Presenting to the Emergency Department

Publication Number: 2529.544

Son H. McLaren, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Carlos A. Camargo, MGH / Harvard University, Boston, MA, United States; Todd A. Florin, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States; Cheng-Shiun Leu, Columbia University, New York, NY, United States; Asuncion Mejias, St. Jude Children's Research Hospital, Memphis, TN, United States; Daniel Green, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Daniel Fenster, Columbia University Vagelos College of Physicians and Surgeons, scarsdale, NY, United States; Marlin Morel, Columbia University Vagelos College of Physicians and Surgeons, New York City, NY, United States; Murad Megjhani, Columbia University Vagelos College of Physicians and Surgeons, Rego Park, NY, United States; Tammam Alalqum, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Oliver Simpson, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Matthew Cheung, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Leslie Blanco, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Yuan Zhang, Columbia University Department of Biostatistics, TENAFLY, NJ, United States; Danielle C. Segarra, NewYork-Presbyterian Morgan Stanley Children's Hospital, Weehawken, NJ, United States; Kam Gong, NewYork-Presbyterian Morgan Stanley Children's Hospital, Brooklyn, NY, United States; Rakesh Sahni, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Soojin Park, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Peter Dayan, Columbia University, Hastings on Hudson, NY, United States

Background: Despite widespread efforts to de-implement low-value care in bronchiolitis, use of non-recommended tests and treatments remains common. Patterns of care among young infants (≤90 days old)-a high-risk group partly excluded from existing guidelines-have not been well characterized.

Objective: We aimed to characterize testing and treatment practices in young infants with bronchiolitis presenting to the emergency department (ED) and to identify factors associated with ED testing.

Design/Methods: In this prospective cohort study, we enrolled young infants with bronchiolitis presenting to the ED. Demographic and clinical data were collected using standardized interviews, and medical records were reviewed to document ED management and hospital course. Outcomes included ED testing (any blood test, evaluation for serious bacterial infections [SBIs], chest radiography [CXR]) and treatment (bronchodilators, antibiotics). Logistic regression was performed to identify independent predictors of ED testing. The model was adjusted for age (≤30 vs >30-90 days), presence of fever, decreased oral intake, degree of respiratory distress, RSV positivity, and, as a proxy for bronchiolitis severity, receipt of respiratory support within 4 hours of ED presentation.

Results: From November 2021-September 2025, 229 infants were enrolled (patient characteristics described in Table 1). On exam, most were well appearing (69%), and in no or mild respiratory distress (72%). More than half (55%) had ≥1 blood test, 31% had evaluation for SBIs, and 19% received a CXR (Table 2). Of the 68 infants who had point-of-care blood analysis, clinicians most often cited baseline respiratory assessment as the indication (81%); results altered planned clinical management in 21% (Table 3). Use of bronchodilators (10%) and antibiotics (10%) was uncommon. Independent predictors (OR [95% CI]) of obtaining a blood test in the ED included presence of fever (4.57 [2.05-10.20]), history of decreased oral intake (2.38 [1.19-4.77]), RSV positivity (2.69 [1.34-5.40]), and receipt of respiratory support (10.56 [3.91-28.54]). SBI evaluation was independently associated only with fever only (36.56 [14.89-89.74]). CXR use was significantly associated with fever (2.52 [1.09-5.81]), moderate to severe respiratory distress on initial exam (4.18 [1.68-10.41]), and receipt of respiratory support (4.79 [1.78-12.93]).

Conclusion(s): Among generally well young infants with bronchiolitis presenting for emergency care, testing was common and driven by fever and illness severity, not age. Overall medication use was infrequent.

Table 1. Patient Characteristics (n=229)
ED: emergency department; RSV: Respiratory syncytial virus.
*226/229 (99%) of infants had viral testing, including testing for RSV. Of 226 infants with viral testing, 221 (98%) had 22-pathogen respiratory panel, and 5 (2%) had 4-plex testing for influenza A/B, RSV, and SARS-CoV-2. RSV negative infants include those who had no detection of respiratory pathogens or tested positive for non-RSV viruses.

Table 2. Testing and Treatment Patterns Stratified by Disposition
ED: emergency department; SBI: serious bacterial infection. Data are expressed as frequencies (%) and analyzed using Fisher or χ2 test.
* Any blood testing includes point-of-care blood analysis, complete blood cell count, and basic metabolic panel. It does not include blood culture.
** Point-of-care blood analysis is generally obtained from a venous sample and includes blood gas, electrolytes, metabolites, and hematology parameters.
† Testing for serious bacterial infections includes obtaining a urine culture, blood culture, or cerebrospinal fluid culture.
‡ Respiratory support includes non-invasive ventilation (continuous positive airway pressure, bi-level positive airway pressure), invasive mechanical ventilation, and high-flow nasal cannula.
§ Supplemental oxygen delivered via any method, including blow-by, standard nasal cannula, face mask, non-rebreather mask, or respiratory support, are included.
|| Bronchodilators include albuterol and nebulized racemic epinephrine.

Table 3. Clinician-stated reasons for obtaining point-of-care blood analysis and its impact on planned management
*Includes point-of-care analysis obtained within the first 4 hours of infant's ED arrival. Clinicians could choose more than one reason for obtaining the test.
**Among those who indicated that results of point-of care blood analysis changed planned management. Clinicians could choose more than one answer for how the test changed planned clinical management.