Factors associated with disease severity in children with bronchiolitis.

Objective: Bronchiolitis is one of the top causes of hospitalization of infants in the United States. Several clinical factors have been associated with hospitalization; however, few studies have examined factors related to severe disease. Our goal was to describe the clinical characteristics and hospital course of children admitted with bronchiolitis and to identify factors related to intensive care unit (ICU) admission in this population.

Methods: We conducted a retrospective review of all children less than 2 years of age admitted to a children's hospital with bronchiolitis between July 2008 and July 2011. Demographic and clinical data were collected including information regarding hospital course, treatments received and respiratory pathogens.

Results: During the study period, 734 children were admitted to the hospital with bronchiolitis, 22% of whom were admitted to the ICU and 10% of whom were intubated and mechanically ventilated. Admission to the ICU was associated with younger age [110 (45-210) days versus 69 (35-149) days, p < 0.001] and history of premature birth (OR 1.7, 95% CI 1.1-2.4, p = 0.01), but not with race or ethnicity. The use of respiratory treatments was common in the children admitted to the ICU but was not associated with shortened durations of hospitalization. In addition, neither prematurity nor young age were associated with either increased duration of hospitalization or with increased likelihood of mechanical ventilation.

Conclusions: During acute bronchiolitis infections, younger children and those with a history of prematurity were more likely to be admitted to the ICU with severe disease.