Predictors of Symptom Rebound in Critically Ill Patients With Croup

OBJECTIVES: There are no data to inform the ideal length of in-hospital observation after symptom improvement or to inform the ideal dexamethasone dose in critically ill children with croup. We describe a cohort of critically ill children with croup who rebound (have return of symptom(s) after meeting hospital discharge criteria) and examine the association between the cumulative dexamethasone dose before PICU discharge and both the odds and timing of rebound. METHODS: In this single-center retrospective cohort study of subjects 6 months to 13 years of age admitted to the PICU with a primary diagnosis of croup, we employed multivariable logistic regression to evaluate the association between cumulative pre-PICU discharge dexamethasone dose and rebound. In the model, we controlled for subject age and sex, insurance, season, and history of prematurity, croup, or intubation. Kaplan-Meier curves were used to compare time to rebound between subjects receiving ≤2 standard (0.6 mg/kg) doses and those receiving >2 standard doses of dexamethasone before PICU discharge. RESULTS: Data were analyzed over 69 months (January 2011–October 2016), and 275 unique subjects met inclusion criteria. The median cumulative dose of dexamethasone in the hospital was 1.57 mg/kg (interquartile range 0.98–2.63). Thirty-seven percent (n = 102) of subjects developed rebound croup symptoms after meeting hospital discharge criteria. The median time to rebound was 13.1 hours (interquartile range 6.1–23.7). There was no association between cumulative pre-PICU discharge dexamethasone dose and the odds (odds ratio = 1.00; 95% confidence interval 0.83–1.19; P = .96) or timing of rebound. CONCLUSIONS: A clinically significant number of critically ill patients with croup rebounded. Total pre-PICU discharge dexamethasone dose did not predict either the odds or timing of rebound.