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Diurnal Variation in Frequency and Severity of Croup in the Emergency Department
Patrick S Walsh1, Matthew J Lipshaw1,2
1Division of Emergency Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
Insights
Children with croup are more frequently seen in emergency departments at night. Nighttime visits show higher racemic epinephrine use but lower hospitalization and ICU admission rates.
Area of Science:
- Pediatric Emergency Medicine
- Respiratory Illnesses
- Epidemiology
Background:
- Croup (laryngotracheobronchitis) is a common pediatric respiratory illness.
- Anecdotal evidence suggests higher emergency department (ED) visits for croup at night, but data are limited.
- Understanding diurnal patterns is crucial for resource allocation and patient management.
Purpose of the Study:
- To analyze the diurnal variation in ED presentations for pediatric croup.
- To investigate the association between the time of ED arrival and clinical outcomes.
Main Methods:
- Retrospective cohort study utilizing the Pediatric Health Information System (2016-2020).
- Inclusion criteria: children aged 3 months to 11 years with croup.
- Statistical analysis using generalized linear mixed-effects models to assess arrival time and outcomes (racemic epinephrine, hospitalization, ICU admission, revisits).
Main Results:
- Significant diurnal variation observed in ED croup visits, with 60.1% occurring at night (8 PM - 8 AM).
- Peak ED arrivals at midnight; nadir at 2 PM.
- Nighttime arrivals associated with increased racemic epinephrine use (OR 1.33) but decreased odds of hospitalization (OR 0.76), ICU admission (OR 0.61), and 3-day ED revisits (OR 0.86).
Conclusions:
- Pediatric croup ED visits exhibit a distinct diurnal pattern, peaking overnight.
- Children presenting at night with croup may require specific treatments like racemic epinephrine but have better outcomes regarding hospitalization and ICU admission.
Background:
Emergency department (ED) presentation for croup is thought to occur more often at night, but evidence for its diurnal variation is sparse. Our objectives were to describe the diurnal patterns of ED presentation in children with croup and to determine whether time of arrival associated with severe clinical outcomes.
Methods:
We conducted a retrospective cohort study using the Pediatric Health Information System. We included children 3 months to 11 years of age with an ED encounter for croup from 2016 through 2020. We quantified ED encounters by arrival hour and used generalized linear mixed-effects models to determine association between arrival time and racemic epinephrine use, hospitalization, intensive care unit (ICU) admission, and revisits.
Results:
There was considerable diurnal variation in ED visits for croup. A total of 126 186 children (60.1%) presented to the ED at night (between 8 pm and 8 am), and 83 763 children presented during the day (39.9%). Peak arrival time was 12:00 am (14 189 encounters) and the nadir was at 2:00 pm (5231 encounters). Children presenting during overnight hours had increased odds of the use of racemic epinephrine (odds ratio [OR] 1.33; 95% confidence interval [95% CI], 1.30-1.36), but reduced odds of hospitalization (OR 0.76; 95% CI, 0.73-0.78), ICU admission (OR 0.61; 95% CI, 0.58-0.68), and 3 day ED revisits (OR 0.86; 95% CI, 0.83-0.90).
Conclusions:
Children with croup present to the ED more commonly at night. Children presenting to the ED with croup at night have greater odds of being treated with racemic epinephrine, but reduced odds of hospitalization, ICU admission, and return visits.
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