Initial nebulized budesonide versus a local off-label nebulized dexamethasone protocol in children with institution-defined grade III croup receiving epinephrine: a retrospective cohort study

Background High-acuity croup requires prompt airway-directed treatment, but evidence comparing nebulized budesonide with a local institutional off-label nebulized-dexamethasone protocol is limited. This internationally unusual route is distinct from standard oral, intramuscular, or intravenous dexamethasone therapy. Methods We conducted a single-center retrospective cohort study of children younger than 12 years hospitalized from 1 January 2014 through 31 December 2023. Pretreatment severity was fixed at the first institution-defined Grade III assessment. We compared initial nebulized budesonide with the local off-label nebulized-dexamethasone protocol among children receiving epinephrine within a prespecified ±15-minute treatment window; corticosteroid administration was time zero. The primary outcome was time to documented resolution of stridor at rest. Stabilized inverse probability of treatment weighting (IPTW) was winsorized at the 1st and 99th percentiles. Results Of 12,480 all-grade croup presentation events, 452 charts underwent full review and 342 met institution-defined Grade III criteria. Three hundred children met all eligibility criteria (150 per strategy); 264 (88.0%) had institution-defined Grade III documented at the first assessment at our center, 36 (12.0%) progressed from Grade II after arrival, and 84 (28.0%) were interhospital transfers. The IPTW-adjusted difference in time to documented stridor resolution was −2.26 h (95% CI −2.63 to −1.89). Intensive care unit transfer occurred in 4/150 versus 6/150 children and intubation in 0/150 versus 1/150; these rare events do not establish equivalent safety. Conclusion Initial nebulized budesonide was associated with faster documented recovery than the local off-label nebulized-dexamethasone protocol after adjustment for measured pretreatment variables. This comparison does not address standard oral, intramuscular, or intravenous dexamethasone therapy and should be interpreted as an adjusted observational association.