545 - Variation in observation time after nebulized racemic epinephrine among children with croup

Publication Number: 2530.545

Irina Topoz, University of Colorado School of Medicine, Aurora, CO, United States; Amanda J. Nickel, Children's Hospitals and Clinics of Minnesota, Minneapolis, MN, United States; Ellen Kerns, University of Nebraska Medical Center, Omaha, NE, United States; Vivian Lee, Children's Hospital Los Angeles, Los Angeles, CA, United States; Gabrielle Z. Hester, Essentia Health, Duluth, MN, United States; Makayla Schissel, University of Nebraska College of Medicine, Omaha, NE, United States; Brittany Jennings, American Academy of Pediatrics, Itasca, IL, United States; Kendall Arslanian, American Academy of Pediatrics, Chicago, IL, United States; Bolanle T. Akinsola, Emory University School of Medicine, Atlanta, GA, United States; Beth A. Condley, University of Oklahoma Fran & Earl Ziegler College of Nursing, Norman, OK, United States; Amy DeLaroche, Children's Hospital of Michigan, Detroit, MI, United States; Daniela Hochreiter, Yale School of Medicine, New Haven, CT, United States; Adolfo Molina, University of Alabama School of Medicine, Birmingham, AL, United States; Amanda Nedved, Children's Mercy, Lenexa, KS, United States; Lisa Schroeder, Children's Mercy Hospitals and Clinics, Olathe, KS, United States; Ryan K. Sewell, Children's Nebraska, Omaha, NE, United States; Randi Trope, Stony Brook Children's Hospital, Stony Brook, NY, United States; Tim Dribin, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Amy Tyler, Nationwide Children's Hospital, Columbus, OH, United States; Kelly R.. Bergmann, Children's Minnesota, Minneapolis, MN, United States

Background: Racemic epinephrine (RE) is administered to children with croup and stridor at rest. While most sources recommended 2-4 hours of observation after RE, the optimal duration is uncertain.

Objective: To describe variation in post-RE observation time and the association between post-RE observation time and return visits.

Design/Methods: This was a secondary analysis of the Better Assessment for Croup in Kids (BARCK) quality collaborative. We collected retrospective data from June 2024 to August 2025 for children 6 months to 6 years of age, discharged from the ED with a primary diagnosis of croup. Children with existing complex conditions and upper and lower airway anomalies were excluded. The primary outcome was post-RE observation time (time between the end of RE treatment and ED discharge). To estimate the association between post-RE observation time and revisits, we used logistic regression with robust cluster standard errors to account for practice correlation. Models were adjusted for age, sex, preferred language, type of care setting, triage severity, time from ED arrival to dexamethasone administration, and the number of RE treatments. Marginal probabilities of revisit were calculated by observation time and number of RE doses.

Results: The study included 5,014 encounters from 57 participating sites (Table 1). The median post-racemic observation time was 144 minutes (IQR 120, 180) for encounters with no revisits and 152 minutes (IQR 123, 189) for encounters with a revisit (Figure 1). Overall, 74.6% of patients were observed for over 120 minutes with a revisit rate of 4.8%; 19.8% were observed 60-120 minutes with a revisit rate of 4.5%; and 5.8% were observed for under 60 min with a revisit rate of 3.1%. In regression analysis, post-RE observation time under 60 minutes (aOR 0.64, 95% CI 0.33, 1.26) or 60-120 minutes (aOR 0.91, 95% CI 0.65, 1.27) was not associated with revisits (Figure 2). The predicted probability of revisit was 3.3% (95% CI 1.3%, 5.3%) for an observation time of under 60 minutes, 4.6% (95% CI 3.1%, 6.1%) for 60-120 minutes and 5.0% (95% CI 4.1%, 5.9%) for over 120 minutes. The predicted probability of revisit increased with the number of RE doses: 4.4% (95% CI 3.5%, 5.3%) for 1 RE, 5.5% (95% CI 4.0%, 7.1%) for 2 RE's, and 13.9% (95% CI 7.2%, 20.6%) for 3 RE's.

Conclusion(s): Revisit rates were similar across observation times but higher among patients who received 3 or more doses of RE before discharge. Our findings suggest that children with croup who require only 1 or 2 RE doses may be safely observed for less than 2 hours after RE treatment.

Table 1: Patient characteristics by observation time after last racemic epinephrine in the ED*
Abbreviation: ED, emergency department; IQR, interquartile range IQR
*Categorical variables compared using Pearson chi-square test and medians compared using Kruskal-Wallis test.


Table 2: Association between observation time after racemic epinephrine and croup-related revisits*
*Logistic regression with robust cluster standard errors to account for within-practice correlation.

Figure 1. Variability in Observation Times After Racemic Epinephrine by Site